Primary network transmission equipment. Industrial practice report

Introduction

technological digital communication

The diploma project examines the issues of reconstruction of the existing communication network. In the context of the dynamic development of the Russian Railways holding, the transition to a new organizational structure “by type of business”, a significant expansion of high-speed and high-speed traffic sections, as well as the development of automation of a number of technological processes, there is a need for reconstruction and updating of the entire transport infrastructure, including field of telecommunication technologies. Reconstruction of the communication network makes it possible to meet not only the needs of railway transport for qualitatively new types of communication, but also in the future - the organization of profitable activities by providing information services to third-party organizations.

At station C of the South Ural Railway, the first stage of reconstruction of the communication network will take place and will be carried out on the basis of modern Broad Gate (BG) equipment produced by ECI Telecom, which combines Ethernet and SDH services. In the future, it is planned to create an optical transport platform on a network-wide scale based on the technologies of dense multiplexing with wavelength division - DWDM (Dense Wavelength Division Multiplexing) and loose multiplexing with wavelength division - CWDM (Coarse Wavelength Division Multiplexing). Phased reconstruction will make it possible, as necessary, to repeatedly increase the capacity of optical lines without interrupting existing connections.

The transition to the BG platform makes it possible to meet the requirements of railway transport in the field of providing modern communication means. This equipment is ultra-highly scalable by connecting expansion modules to standard BG modules and provides Ethernet over WAN/MAN networks. High traffic stability due to redundancy of basic hardware and tributary protection ensures increased reliability and uninterrupted operation of all types of communications used in freight and passenger transportation.

Reorganizing the network through the introduction of BG equipment is justified from the point of view of saving capital costs, since a significantly smaller amount of equipment is used and the bandwidth is optimally used. In addition, lower operating costs are achieved due to the cost-effective integration of Ethernet and SDH into one platform with a single management system. Along with data transmission, the BG platform provides various Ethernet services via a single physical port, Layer 2 data application functions, and EoS (Ethernet over SDH) technology.

.Existing communication scheme of station C

.1 Characteristics of the site and station

It is planned to reorganize communications at station C on the South Ural Railway. The South Ural Railway occupies a favorable economic and geographical position.

South Ural Railway is one of the branches of JSC Russian Railways. The railway runs through the territories of Orenburg, Chelyabinsk and Kurgan, as well as partly through the Sverdlovsk region. The road management is located in Chelyabinsk.

In the Southern Urals, industrial sectors are quite developed: mechanical engineering and metalworking (a large share of the defense industry, agricultural and road-building machines, light industry and processing of agricultural products); production of building materials (prefabricated reinforced concrete products, wall materials), primarily an industrial region. All industrial products are mostly exported outside the region.

To date, due to the high level of industrial development of the region, all main directions of the railway have been converted to electric traction, which allows them to successfully cope with large cargo flows. The most heavily loaded section of the road runs from east to west, connecting regions of Siberia and the Far East with the western regions of the country. In winter, this is mainly freight traffic, and in summer the number of passengers transported increases sharply. The main types of cargo are minerals mined not only in this region, but also in neighboring areas, timber, imported raw materials for industry, export of finished products of the defense industry, agricultural machinery, engineering and agricultural products, a large volume of transit transportation of coal and metals , petroleum products, timber.

Station C was opened in 1952. It is an intermediate station. 3rd class station. Has 7 tracks, was electrified in 1953.

The station is located on a section of the B-M-1 railway line, a double-track section with a length of 165 km is equipped with automatic blocking and is electrified. At this site, to organize the transportation process and resolve other operational issues, the following types of operational and technological communications are organized: PDS, EDS, SEM, PS, LPS, LBK, MZhS, PGS, VRS, PRS.

Control dispatch communication stations (DST) for EDS, EMS, LPS, VRS, and control station communication stations (PST) for PS and LBK are located at station B.

At the station, the main, road and departmental operational-technological communications and public telephone network are organized along existing communication lines using a fiber optic cable.

The following types of communications are connected to the station attendant's console (DSP): PDS, PRS, EDS, LPS, PS, MZhS, PGS.

At the station, communication is organized via fiber-optic communication lines using Ob-128Ts equipment.

1.2 Equipment set for cabinet “Ob-128Ts”

The main set of equipment includes a specialized primary multiplexer (controller) SSPS-128 and a NEAX 7400 switching station. The equipment is located in the Ob-128Ts cabinet shown in Figure 1.1.

Figure 1.1 Cabinet “Ob-128Ts”

The SSPS-128 converter provides the formation of group channels of dispatch communications in the linear digital stream E1, branched using digital adders to the switching station, the allocation of direct non-switched PM channels with analog branches (PRS, MZhS, PGS, etc.), data transmission channels, as well as analog branches from group dispatch communication channels.

According to the communication development concept of JSC Russian Railways, the entire Russian railway network is divided into separate regions. Each region is assigned to a specific equipment manufacturer. The South Ural Railway uses Ob-128Ts equipment. This equipment marked the beginning of the development of telecommunication networks, but recently the requirements for flexible equipment configuration, its versatility, ease of implementation and maintenance, control and administration capabilities have increased. Figure 1.2 shows the placement of communication equipment at the station before the reorganization.

Figure 1.2 Layout of equipment at station C before reorganization

1.3 Radio communication cabinet equipment

In the communication center room at the station, Figure 1.2, in the radio communication cabinet, the RS-46MC HF, RS-46MC VHF radio stations and the RI-1M voice informer are installed.

The RS-46MC radio station is shown in Figure 1.3. The radio station provides control via a linear communication channel from the control station and from control panels, which can be located either directly at the installation site of the radio station or at a distance of up to 20 km via physical lines or using communication channels.

Figure 1.3 Radio station RS-46MC

In the HF band, the radio station provides operation in single-frequency simplex mode at one of two frequencies 2.130 and 2.150 MHz. In the VHF band, the radio station provides operation in single- and dual-frequency simplex mode on any of 171 operating frequencies in the range from 151.725 to 156.000 MHz with a frequency spacing between adjacent channels of 25 kHz.

The power supply provides power to the radio from the main and backup primary sources. Switching from the main source to the backup source and back occurs automatically. Table 1.1 presents the technical characteristics of the radio station.

Table 1.1-Technical characteristics of the radio station

Name VHF band HF band Operating range, MHz 151.725 -156.0002.130 and 2.150 Nominal transmitter power (reduced), W 8-10 (1, 3, 5, 7) 10-14 Modulation type F3 E Operating frequency grid step, kHz 2520 Receiver sensitivity, μV0 .55Power consumption , W, no more - in standby reception mode 25 - in transmission mode 70 Main power source, V220 (-33...+22) Backup power supply, Rechargeable battery Dimensions, mm 298x256x249

The radio station has the following functions:

Connecting to a linear channel, disconnecting from it and controlling the “RECEIVING” and “TRANSMITTING” modes according to commands from the control station;

transmission to the control station via a linear channel of a connection control signal containing information about the assigned number of the connected radio station, and disconnection from the linear channel upon the “END END” command from the control station;

Transmission over the radio channel of a calling signal with a tone frequency of 1000 Hz after connecting to the linear channel at the command of the control station in two ways: automatically after connecting the radio stations to the linear channel and broadcasting from the control station (set during configuration);

Automatic disconnection from the linear channel 60 s after the termination of control of the radio station by the control station;

connection to a linear channel when receiving calling signals from the radio channel at frequencies of 700 and 2100 Hz; broadcasting a call to the control station with a code corresponding to the frequency of the received call, and transmitting a call acceptance control signal to the radio channel with a tone frequency of 900 Hz and a duration of 0.8 to 1 s;

analysis of the quality of the radio channel when receiving calling signals from moving objects and ensuring connection to the linear channel of only one stationary radio station, which has the highest level of useful signal, in the case of receiving calling signals by several radio stations;

controlling the radio station and conducting negotiations from one or two control panels;

control of the radio station and transmission of information from TU-TS devices;

issuing a low-frequency signal for recording conversations conducted through a radio station.

The selection of a radio station that connects to a linear channel is ensured by comparing the levels of high-frequency signals acting at the inputs of radio station receivers that received a calling signal from a moving object. The “best” radio station is the one that has the highest level useful signal at the receiver input.

The radio station has three operating modes: “STANDBY RECEPTION”, “RECEIVING”, “TRANSMITTING”.

When operating in the “STANDBY RECEPTION” mode, the radio station processes call signals coming from the radio channel. In this case, speech information and calling signals existing in the radio channel should not be heard in the loudspeaker and telephone of the console.

When operating in the “RECEIVE” mode, calling signals and conversations conducted over the radio channel are heard in the loudspeaker and telephone of the remote control.

When operating in the "TRANSMITTING" mode, the transmitter is turned on, and all information received by the transmitter modulator from the control unit and other sources is transmitted to the radio channel.

The radio communication cabinet also includes a voice informant. RI-1M is presented in Figure 1.4 and is intended for generating warning signals in the form of speech or tone signals and subsequent transmission through radio communications or public address systems.

Figure 1.4 RI-1M voice informant

An alert signal is generated automatically when there is an event at the device inputs. The logical connection between an event and an alert signal is established programmatically using special software (SPRS). An event is a change in the state of a contact sensor (for example, relay contacts) or the receipt of special commands from an expansion unit (external CS event controller or BS matching unit). Events can be parameterized or fixed. The device is a synthesizer of audio signals and has an 8-channel device for polling contact sensors, an interface (RS-485) for communication with expansion units, a communication circuit for a radio station (PCT) or broadcast ULF. In addition, the device has an external loudspeaker unit (BVG) for monitoring the alarm signal.

Figure 1.5 shows a diagram of the RI-1M voice informant warning system. This system has shown its reliability and has been used on the railways of the Russian Federation for more than 10 years.

Figure 1.5 Alarm system diagram

The use of contact sensors makes it possible to generate fixed speech messages without indicating quantitative indicators. Intelligent sensors together with a matching unit make it possible to increase the information content of voice messages indicating quantitative parameters. The parameters are given in table 1.2.

Table 1.2 - Parameters of the voice informant RI-1M

No. Parameter Value 1231 Number of input channels or recorded events - with additional block KS-1 8 2 Frequency of the calling tone for the radio station, Hz 1000+-53 Duration of the tone, sec 34 Number of repetitions of tone and speech signals 25 Initial state of contact sensors normally closed 6 The level of the output low-frequency signal of the RI-1 m block is adjusted at the load 6 00 Ohm within, mV40...6007 Length of the communication line with contact sensors, m, up to 20008 Length of the communication line with the radio station, m, up to 39 Length of the communication line from the RI-1 unit to BVG, m, up to 15010 Length of the communication line from the RI unit to the KS, BS units m120011 Power supply of the unit RI-1 m from the network: - voltage, V - frequency, Hz - power consumption, W, no more than 220+10%-15% 50+-1 2512 Dimensions, mm210x90x11013 Weight, kg2.5

The device provides reliable galvanic isolation from sensors, expansion units, and communications.

Programming of voice messages is carried out using special software. A simple interface allows you to assign a separate voice message and (or) tone audio signal to each polling channel of a voice informant or expansion unit. In order to save memory, speech messages of the same type can be formed from separate fragments, which can be recorded using any sound editor and saved in 16-bit format (WAV or RAW) before compilation. Then the necessary messages are formed from the phonemes, and a binary (BIN) file is compiled for flashing into the ROM of the speech informant. Next, using the programmer, the data is entered into ROM, which is installed in the corresponding socket on the RI-1M board.

.4 TCC cabinet equipment

In the premises of the communication station C in Figure 1.2 there is a network clock synchronization cabinet (TNS), which includes the RS TSS-M, URSS.

A clock distribution device is shown in Figure 1.6 and is a network clock synchronization equipment (SASE) designed to distribute synchronization signals (SS) to the required number of outputs when there are one or two input CCs (2048 kHz or 2048 kbps). URSS provides conversion of the E1 stream (PTSK-E1-2048 kbit/s), by rewriting information to a new clock frequency that has the stability of the “main” SS (from those arriving at the input of URSS), and the formation of the E1/T stream.

Figure 1.6 Synchronization Distribution Device

Main characteristics of the device

Input reception of up to 2 synchronizing signals (SS) 2048 kHz or 2048 kbit/s (E1) with an input impedance of 120 or 75 Ohms (according to operator settings);

Implementation of the function of converting the E1 stream into the E1\T stream (E1\T is the E1 stream, at the output of the PS/PS2 clock signal conversion block, rewritten via the clipboard to the frequency of the “main” input CC, i.e., implementing the retiming function).

Formation of 1 to 4 PCC E1\T (R out 120 Ohm) 2048 kbit/s with stability determined by the stability of the designated “main” input SS 2048 kHz or 2048 kbit/s;

The conversion clock frequency is 2048 kHz, allocated from the designated “main” input CC;

The number of synchronization signal outputs 2048 kHz or 2048 kbit/s (E1) is no less than 4 and no more than 8 with the possibility of pairwise change of SS type (2048 kHz or 2048 kbit/s);

Possibility to select the flow structure at the device output: PCM-30 or PCM-31, ability to enable/disable the CRC-4 procedure;

The ability to expand the load capacity of the equipment by connecting to this (master) Device a similar one or two slave devices, while maintaining all the outputs of the master Device, without the use of additional external CCs. The remoteness of installation of slave Devices is determined by the requirements for the level of the input signal of the URSS.

When input clock signals are received from the PEG, the values ​​of MOVI (maximum error of the time interval), DVI (deviation of the time interval) and jitter (Jitter) at the output of the URSS comply with the requirements of G.811

There is a local indication: about the presence of input SS, supply voltages, about a failure of any unit, about the loss of SS or any E1 and E1\T flow, about the presence of slips, there is a generalized accident signal transmitted by “dry contacts” to the service station;

It is possible to control any output CC (2048 kHz or 2048 kbit/s) or E1 stream that has undergone conversion (E1\T), without disconnecting consumers at a separate control socket;

Dimensions: URSS 483x87.2x317

The weight of the fully assembled URSS is no more than 3 kg.

Power consumption no more than 15 W

DC power supply with a voltage of 36-72 V with a grounded positive pole and 100% redundancy.

A big advantage of the equipment is the presence of up to 8 independent CC outputs of 2048 kHz or 2048 kbit/s with the ability to control any output without disconnecting CC consumers.

The network clock synchronization signal splitter Figure 1.7 is intended for use in communication network nodes to provide all node equipment that requires synchronization with the necessary clock signals.

Figure 1.7 Network Clock Splitter

The use of RS-TSS-M allows you to obtain a large number of synchronization signals without the cost of upgrading already installed equipment. Technical characteristics are given in table 1.3

Table 1.3-Technical characteristics of RSS-TSS-M

Functional characteristics ValueInputs clock signals 2048 kHz (ITU-T G.703/13)3 (the priority of the input clock signal corresponds to the input number) Number of outputs From 8 to 16 Type of output signals 2048 kHz (ITU-T G.703/13) or 2048 kbit/s (ITU-T T G.703/9) Characteristics of the quality of synchronizing signals Phase jump when switching inputs less than 15 ns Phase wander generation (MOVI) less than 1 ns Technical parameters Input impedance 120 Ohm or high-impedance (configurable by technical staff) Power supply voltage from -38.4 V to -72 V, there is a main and backup inputPower consumption less than 4 W

The front panel has LED alarm indication of the status of inputs and outputs, as well as a connector for connecting a rack-wide alarm.

The splitter does not require the cost of organizing additional consoles and technical operation workstations. The resistance ratings for each input and the types of output signals (2048 kHz or 2048 kbit/s) are selected by installing jumpers on the plinth on the front panel of the device.

The TCC cabinet also includes a power distribution panel (PDB), a GIE4805 modular power supply, which is designed to provide uninterrupted 48V power to compact telecommunications centers, satellite communication stations, radio relay equipment, low-power switching equipment, mobile communication base stations of GSM / WCDMA standards, and other telecommunications and industrial equipment. The device consists of a power supply with a set of rectifiers. The TCC cabinet includes voltage stabilizers SPN 48-24 and are intended for power supply of devices and telecommunications systems with a stabilized voltage of 48 or 24 V DC and can be used as independent products as part of power supply installations or installed in racks (racks) of DC voltage stabilizers (SSPN)

Stabilizers provide:

Regulation and stabilization of output voltage;

local signaling about normal operation of the stabilizer;

load current limitation and local alarm in case of overload and short circuit in the load;

protection when the output voltage increases and when the input voltage decreases;

remote signaling in case of stabilizer malfunction;

possibility of parallel operation of stabilizers for a common load;

After the emergence of new systems, to increase the capacity and reliability of the devices, it is necessary to reorganize the old equipment and add new equipment, such as the recent appearance at station C of the new dispatch centralization system DC-YUG with RKP. The system is designed to automate the processes of monitoring and controlling the movement of trains on sections and directions of the railway, providing the possibility of information interaction with related automated control systems at the industry, regional and road levels, testing and diagnosing technical equipment through the use of modern telemechanics, microelectronics and computer technology.

2. Purpose of reorganization

2.1 Implementation of systems DC "YUG", APK DC, SPD LP

To increase the capacity of trains, the railway is introducing a new DC system "YUG", to install this system it is necessary to install an additional module in the SMK-30 multiplexer. DC "YUG" is a key link in the integrated transportation management system: on the one hand, it provides a real-time information picture of the systems GID "URAL", OSCAR, AS TSUMR, ADC SCB, etc., and on the other hand, it effectively uses the information of these systems for constructing a holistic representation of the train information model. DC "YUG" allows you to build structures with linear and branched topology and two-channel communication organization. The system automatically adapts to the quality of communication channels, optimally routing information flows taking into account the use of both channels and automatically rebuilding the configuration in case of failures, which ensures a high level of its survivability.

The introduction of a new system of hardware and software complex for dispatch control (APK DC) forms a computer network to provide operational information to the dispatch apparatus of the road department, road management and linear enterprises. The use of computer technology made it possible not only to expand the capabilities of the system for the train dispatcher, but also to solve the main problems of monitoring the state of technical means of automation systems at hauls and stations of the dispatch area. APK-DK equipment is designed to transmit information to the train dispatcher:

About the location of trains within the control circle:

control of vacancy and occupancy of block sections, main and receiving and departure tracks of intermediate stations;

indications of entrance and exit traffic lights;

the established direction of movement (on single-track sections equipped with AB);

condition of crossings and temperature of rolling stock axle boxes.

At the same time, APK-DK performs the tasks of technical monitoring of the condition of automation devices at hauls and stations. All information is received in real time. The control result is transmitted to the mechanic on duty, the signaling and communication distance manager, and then to the technical personnel responsible for collecting and processing failure statistics. The system allows you to increase productivity and improve working conditions of traffic control dispatchers at the level of regional control centers. New systems require additional equipment, since previously installed equipment cannot solve the problem of placing new systems.

At the station, it is planned to install an additional module in the SMK-30 multiplexer in the diploma project for connecting to the data transmission system of linear enterprises. SPD-LP is designed for automated collection, centralized collection, processing, transmission and distribution of operational, including diagnostic, information to consumers in real time. The network transmits data on the state of linear technological facilities, technical means and systems of automation, communications, and energy; devices for monitoring the condition of rolling stock while the train is moving (PONAB, DISK). Users of this network, unified for all services, are traffic service workers (station attendants, train dispatchers, department attendants, etc.), power supply, signaling and communications workers, etc.

SPD-LP is built on the basis of information concentrators (CI) and linear controllers (LC) connected to the concentrators. In turn, terminal devices of controlled objects are connected to the LC. According to its technical characteristics, SPD-LP belongs to the class of distributed networks with packet switching and the use of dedicated telephone communication channels and optical and radio communication lines for information transmission.

Centralized collection, accumulation and storage of primary information is carried out on a common SPD-LP server included in the local computer network (LAN) of the information collection center. The same LAN includes the workstations of SPD-LP users (dispatchers, duty officers and other service workers), who receive the information they need from the SPD-LP server.

.2 Redundancy of communication systems

The high level of reliability of modern optical communication networks is ensured by the implementation of a set of various measures, among which one of the key ones is the means of full or at least partial restoration of communication in emergency situations. For this purpose, redundancy is used - the purposeful introduction of a certain redundancy into the system in order to increase the degree of connectivity of its individual nodes, that is, the number of independent paths for transmitting information. By order of the head of the road, after the implementation of new control systems, it is necessary to make a reservation.

Fiber optics and optoelectronics are widely used in the construction of all levels of communication networks: long-distance and urban communication trunk lines, access networks and structured cabling systems. Due to the importance of the tasks solved with their help, very high requirements are placed on reliability. In this case, reliability is understood as the ability to maintain the transmission of information at a given speed and with a given reliability for the required period of time. Options for increasing network reliability using redundancy are inevitably associated with additional costs.

Emergency situations in the linear part of the network in most cases arise due to mechanical damage (breaks) of the optical fiber, so the obvious solution to this problem is to increase the number of available physical transmission paths that will be switched to when a fault occurs. Technically, this is achieved by increasing the number of light guides above the minimum required value. This technique is called linear reservation.

In our case, backup fibers are allocated in the same cable as the main ones. The overall reliability of the network increases significantly if the fibers of the main and additional paths are in different cables. These cables are laid on different routes to minimize the risk of simultaneous failure. Such an improvement in the technical characteristics of the network leads to an increase in the costs of its implementation. The thesis project Figure 1.1 involves 15 and 16 fibers. After the reorganization, 2 more fibers 13 and 14 will be used to increase network reliability.

Linear redundancy can be organized according to 1+1 and 1:1 schemes. When using the first scheme, information is transmitted simultaneously along the main and backup paths.

When accessing a 1:1 scheme (Figure 2.1), additional circuits do not carry useful information, but are always ready to take over its transmission, that is, they are in hot standby mode. The main path is usually the shortest route or path with minimal attenuation.

Switching to standby is carried out by an alarm signal, which the control system issues when there is a complete loss of communication or a predefined bit error rate limit is exceeded. The switching duration for SDH networks should not exceed 50 ms.

Figure 2.1 1:1 redundancy scheme

After completing repairs to the damaged area, in most cases the original network configuration is restored.

In addition to using the 1:1 scheme (100 percent redundancy), it is permissible to organize redundancy according to the m:N scheme, when there are m backup circuits for N main transmission circuits. In case m< N резервирование уже не является 100-процентным. В данной ситуации резервируются только те оптические тракты, по которым осуществляется передача сигналов наиболее значимых информационных сервисов.

Redundancy in optical communication systems is an objective necessity and is used to increase the reliability of data transmission at all levels of modern information communication networks.

The overall reliability of the network increases if system redundancy is used, since it provides protection both in case of damage in the linear part and in case of failures of the active equipment of the nodes.

.3 New technical features

The new information age has caused a significant increase in telecommunications services. The largest of which is the Internet. In the new environment, more and more services are provided to end users at the access level. At the same time, DWDM (Dense Wavelength Division Multiplexing) optical channel multiplexing technology makes it possible to efficiently transmit huge amounts of information over global networks, and SDH technology provides reliable means of data transmission. In the existing network, access limits further growth in traffic volumes and the use of various technologies and does not allow satisfying user requests for the provision of new services and reducing their costs. The need for data exchange over global networks and access networks is constantly increasing. Distributed organizations are looking to extend their Ethernet-based LANs to connect the organization to the Internet.

As the number of LAN-centric applications increases, backbone and service providers are looking for new opportunities to increase communications capacity. As application bandwidth demands increase, access networks increasingly need adaptable and expandable equipment that can perform their functions transparently and provide flexible network bandwidth allocation.

For this purpose, a multiservice platform is used. The BG-30 platform allows you to effectively use the installation infrastructure of SDH networks and increase the number of services provided. Thanks to its expandability, wide range of networking capabilities and security, this platform increases the cost-effectiveness of operating networks. BG-30 allows you to respond in a timely manner to the need to expand your network. The multiplexer supports Ethernet, SDH, PDH (Plesiochronous Digital Hierarchy) and PCM technologies, which provides companies with new commercial opportunities.

The emergence of new software and hardware tools for automated workplaces will make it possible to remotely configure and control equipment at the station, as well as improve the safety of train traffic. The automatic workstation of the station duty officer is supposed to be used to solve problems related to the technological process of work carried out by operational personnel, to receive, display and store information about the train position at controlled stations, identify and track mobile units, and notify people working on the tracks. The use of DSP automated workstations will allow:

1. Increase traffic safety by:

Constant monitoring of the train position at stations and stages;

analysis of emergency situations using Black Box data.

2. Increase the efficiency of using communication channels;

supplying the necessary information about the state of devices and the movement of trains of other technological ASDK automated workstations - DSP automated workplace, DNTs (U) automated workplace, TCHD automated workplace, etc.

the possibility of transmitting arbitrary information via ASDC channels;

transfer of all information from DSP automated workstations and DC controllers to the DNC automated workstation.

3. Project for reorganizing the communication network at station C

3.1 Construction of a digital network at station C

The purpose of reorganizing the communication network is to increase capacity and improve the reliability of communication systems through redundancy. For redundancy, an additional SMK-30 is installed. The implementation of new systems of the DC "YUG", SPD LP requires additional redundancy in the event of a breakdown of the SMK-30 multiplexer. So, to reorganize communication equipment into the previously installed SMK-30, a 6SMGC-4 module with a G.703 interface is installed. Thanks to the G.703 interface, the equipment can operate at data rates of 64 Kbps, 1544, 6312, 32064 and 44736 Kbps (PDH, American version), 2048, 8448, 34368, 139264 Kbps (European version). Twisted pair (Z=100-120 Ohm) or coaxial cable (75 Ohm), pulse amplitude 1-3V, is used as a physical transmission channel. At a speed of 64 Kbit/s, three types of signals are transmitted through the interface: information (64 Kbit/s) and two synchronizing clocks 64 Kbit/s and 8 Kbit/s.

The thesis project plans to install meeting communications in the station manager’s (DS) office. To do this, module 13 SMTS-4S will be installed in the SMK-30 multiplexer. Thanks to this module, it becomes possible to conduct video meetings online in the station master’s studio, which saves time and money on traveling to meetings in another city. The remaining modules in the main multiplexer remain in the same composition. It is also necessary to install a backup multiplexer SMK-30 to back up the main one. Radio stations RLSM-10-45 will be installed in place of old radio stations with minimal labor and economic costs.

According to the diagram, RLSM-10-45 KV will also be connected to the SSPS-128 controller via port 1IS-4. IS-4 - kit for connecting four-wire PM channels.

The second radio station RLSM-10-45 VHF according to the scheme will be connected to the backup multiplexer SMK-30 to the 1SMA4-4 module. Replacing radio stations is economically feasible.

The hierarchical construction of the communication system at the station provides for the presence of a three-level communications structure, and involves the inclusion of part of the already existing and newly constructed information transmission systems.

At the first level, the SDH network is used as backbone switching channels. In the communication center, the main input/output multiplexer will be the BG-30, which connects backbone fiber-optic communication lines with a capacity of 155 Mbit/s. And SMS-150C will work as a backup. These I/O multiplexers provide high-speed network access at 2048 kbps streams to the next layers of the communication system.

At the second level, the creation of a group channel and the connection of a number of subscribers of various types to it are ensured. This ensures compatibility of the interfaces with existing analog equipment. The used SSPS-128 converters have a maximum capacity of 128 ports, and interfaces E1, PM, IS-4, DSU, PGS.

Also at the second level it is planned to use the Asmi-52 modem connecting to the EChE Tur and PPS modems for data transmission. Asmi-52 modems use SHDSL technology with TC PAM-16 line code, which allows you to increase the range of digital communication lines. Provide data transmission over long distances at speeds up to 2.3 Mbit/s over one copper pair and up to 4.6 Mbit/s over two pairs.

At the second level, a Cisco 2811 router will be installed, which will meet the needs of workplaces for modern communications. The router has a high level of security. Uses hardware encryption when connecting to VPN and WAN networks.

At the third level, switching equipment is used that uses NEAX7400 digital stations with a capacity of 64 to 512 ports, interfaces: E1, analog and digital subscriber sets. Its task is to ensure the functioning of consoles and other OTS subscribers, as well as their interaction with the second level. In addition, at the same level, interstation communication and general technological communication of the road are organized. The SSPS-128 converter allows, at low cost, to solve the problem of harmonizing any foreign PBX and trunk radio communication systems with the public telephone network of Russia and other countries.

The SSPS-128 converter, depending on the equipment configuration, can change its functionality from a multiplexer-concentrator of subscriber terminals to a signal system converter for digital connections or a tariff system.

Most of the settings when putting the system into operation and ongoing maintenance are made programmatically from the operator console, which is either an IBM/PC compatible computer connected via an RS-232 interface with the appropriate software, or remotely via a modem.

The use of powerful DSPs makes it possible to process signal traffic of tone signaling systems without blocking, as well as to conduct total monitoring of the call on channels connected through the city subscriber line interface.

The system has a space-time non-blocking switch, which allows you to effectively distribute conversational traffic between channels taking into account the following criteria: line type, time, cost.

Purpose of the SSPS-128 converter:

group channel controller;

a control device interacting with a digital transmission system;

switching and channel-forming equipment with dedicated central control center, central communication center, data transmission channels;

provides access to the group channel for switching station subscribers;

includes connection equipment:

a) 4-wire PM channels;

b) 2-wire terminations for organizing analog branches from the digital network via physical lines;

c) 2-wire terminations for organizing communication via physical communication lines;

d) 2-wire terminations for connecting MZhS lines;

e) radio stations;

g) negotiation registrars.

Digital NEAX 7400 ICS, also part of the Ob-128Ts complex, meet modern requirements for communication systems and work with any type of information - speech, data, text, video signal.

NEAX 7400 series private PBXs make it possible to provide a number of complex functions through the use of computer technology and the connection of additional peripheral devices. In particular, functions such as detailed call recording (SMDR), voice messaging (MCI), automatic switching (ACD/MIS), maintenance (MAT), as well as adaptation of the system to the specific tasks of a given user (OAI) are possible. In addition, it is possible to introduce voice messages and background music for the response waiting mode. All these devices provide system flexibility and high efficiency.

The logical structure of the OTS network is formed by two rings: SSPS-128 converters connected by ISDN channels and NEAX7400 stations connected by SS No. 7 channels to each other. In this case, the converter and stations are connected in pairs. The logical structure of the OTS network is shown in the figure

ISDN signaling is used to exchange information between SSPS-128 converters and NEC digital stations. SS No. 7 signaling ensures data exchange in the network between NEC digital stations.

It is assumed that the SSPS-128 converter ensures the functioning (controls) of its own subscribers (subscribers of existing analog subsystems) and subscribers connected to the NEAX 7400 ICS station, Figure 3.1.

Figure 3.1 Organization of OTS and OTS at the station

.2 Fiber optic cable

The station uses fiber optic cable (FOC) with a capacity of 16 single-mode fibers with the following distribution;

4 OB - STM-4 with linear redundancy 1+1;

6 OB - for departmental communications;

4 OB - reserve and mutual exchange with other operators of an interconnected communication network.

In 2013, an optical cable was laid that will be used in our diploma project, since the goal of the reconstruction is to increase the throughput and reliability of systems with minimal investment. At the station, the cable was laid in the ground. This method provides the greatest reliability. At stations this method should be mandatory. The station uses cable brand

OKB - S - 6/2 (3.0) T - 16 (2)/8 (5) (Figure 5.1) JSC TransVOK.

Explanation of the cable brand:

OKB fiber - optical communication cable armored with round steel wires;

outer shell made of polyethylene;

C - protective covers made of round steel wires;

inner shell made of polyethylene;

6 - number of optical modules;

Number of filling modules;

0 - nominal outer diameter of modules, mm;

T - central power element - steel cable covered with a polymer sheath;

Number of standard single-mode optical fibers compliant with G.652 recommendation;

Number of single-mode zero-dispersion-shifted optical fibers compliant with G.655 recommendation;

Figure 3.2 OK design

Table 3.1 shows the technical characteristics of the cable.

Table 3.1 - Technical characteristics of the OK cable

Parameter Unit of measurement Value Number of optical fibers in a cable pcs. 2 - 96 Maximum number of optical fibers in one module pcs. 12 Type of optical fibers, according to the recommendations of ITU-TG.651 G.652 G.652С G.655 Attenuation coefficient, no more, at wavelength: λ=1310 nm λ=1550 nmdB/km 0.36 0.22 Cut-off wavelength, no more than 1270 m Chromatic dispersion, no more, in the wavelength range: (1285-1330) nm (1525-1575) nmps/ (nm × km) 3.5 18Calculation weight kg/km 320 - 2300 Permissible tensile force kN 7.0 - 80.0 Nominal cable diameter (D cab )mm13.9 - 28.2 Operating temperature°C-40… +70 Installation temperature°C-10Minimum permissible bending radiusmm20 D cab Standardized construction length, not less than km6.0

Peculiarities:

Service life - at least 35 years;

Modular design;

The presence of protective covers (steel wire armor), a central strength element (fiberglass rod or steel cable covered with a polymer sheath);

Resistant to damage by rodents;

It is possible to manufacture with an outer shell made of flame retardant polyethylene;

It is possible to produce construction lengths up to 6 km;

Marking of linear meter with an accuracy of at least 1%;

Supplied on wooden drums types 12a, 14g, 17a, 18a.

This cable will be used to modernize the station. It is assumed that 4 fibers from this cable will be used.

.3 Primary network transmission equipment

Fiber-optic communication lines are laid along the railway using STM-16 transmission systems (2488.32 Mbit/s). At the project station, it is planned to have network nodes with synchronous input/output multiplexers SMS-150C and BG-30 with cross-connector functions, providing branching of high-speed streams of 155 Mbit/s, interaction of STM-1 and STM-16 of the lower level and allocate the required number of E1 streams. According to the project, 5 E1 streams and 17 E1 BG-30 streams will be allocated in SMS-150C.

All equipment is covered by the TMN control system. The local network subscriber terminals are included in the switching equipment of the secondary network, which is connected to the primary network through E1 joints.

The main purpose of STM-1 is to provide E1 flows to secondary networks at the road and department levels. At the backbone level, a more powerful STM-16 transmission system is used to interconnect road nodes and for STM-1 redundancy. The allocation of the required number of E1 streams from STM-1 is organized by synchronous input/output multiplexers. The primary communication network, which is the basis of the network, determines its main characteristics: reliability, throughput, controllability.

On the basis of the primary digital communication network, a secondary communication network is formed to organize general technological communications, operational technological communications and data transmission.

In accordance with what is written above, to organize the primary digital communication network of the road level in the diploma, it is planned to install the main input/output multiplexer of the BG-30 brand from BroadGate and will be used for redundancy SMS-150C.

3.4 I/O multiplexers BG-30 and SMS-150С

The SMS-150C is a third generation Synchronous Digital Hierarchy (SDH) multiplexer designed as part of NEC's SDH series of products. It utilizes the STM-1 multiplexer functionality to provide greater versatility in networking applications. The specific functions of the SMS-150C are determined by configuration.

Multiplexer of the SDH transmission system type SMS-150C, operating on two fibers with a digital flow of 155 Mbit/s. It provides allocation of up to 21 E1 streams.

The stations will have 7 E1 streams in each direction.

E1 streams allocated by the SMS-150C multiplexer are used for the technological communication network (OTS, ObTS and PD):

Features of SDH multiplexer SMS-150C:

compact size for mounting in a closet;

allocation of up to 21 channels 2Mbit/s (G.703);

X fiber SNC-P ring redundancy with path redundancy at VC-12 and VC-3 levels;

supports terminal multiplexer mode with linear traffic redundancy 1+1 MSP;

allows performance monitoring (G.826);

has the function (ALS) of automatic laser suppression (G.958);

equipped with an external synchronization signal input;

allows you to download software remotely;

equipped with alarm interfaces for the state of the room (NSA) and monitoring the state of the room (NSC);

The SMS-150C multiplexer is located in the Ob-128Ts equipment cabinet, which is located at station C.

The BG-30 is a multiplexer of STM-1 - STM-16 levels, both terminal and I/O topologies. The BG-30 provides PCM, TDM, 10/100 BaseT and GbE data interfaces. Ethernet traffic is located in n*VC-12/VC-3 containers using standard VCAT and LCAS. BG-30 Figure 3.3 is a more powerful, scalable platform that can effectively expand the existing networks of both medium and large enterprises according to needs. The uniqueness of the BG-30 multiplexer also lies in the fact that it completely allows the capacity of the STM-16 channel to be utilized using EoSDH technology using a 1U form factor.

Figure 3.3 Multiplexer BG-30

The BG-30 multiplexer consists of:

2U BG-30E - expansion platform

64xVC-4 cross-connect matrix

Client interfaces from STM-16/GbE to 64Kbit/s: STM-1/4/16, E1, E3/DS3, FE, GbE, FXS, FXO, 2W/4W E&M, V.35, V.24

BG-30B Ethernet: L1/L2 with QoS and GFP/LCAS

1U BG-30B - basic platform

The BG-30 also operates under LightSoft's multi-dimensional network control system. Network transceivers are used to transmit and receive signals between two physically different media in a communication system. The selection of the transceiver is carried out in accordance with table 3.2. Transceivers of different types can be installed in one system module.

Table 3.2 - Laser optical transceivers

10, dRange (including margin for aging and connections), kmS 1.1STM-11310-15… - 8-28 (-30)0-50 (0-65) L1.1STM-11310-5…0-34 (-36) 10-80 (10-90)L1.2STM-11550-5…0-34 (-36)20-130 (20-143)S 4.1STM-41310-15… - 8-28 (-30)0-30 (0-48)L4.1STM-41310-3…+2-28 (-30)10-70 (10-85)L4.2STM-41550-3…+2-28 (-30)20-110 (20 -136)S 16.1STM-161310-5…0-18 (-20)0-15 (0-36)L16.1STM-161310-2…+3-27 (-29)10-60 (10-80) L16.2STM-161550-2…+3-28 (-30)20-90 (20-129)

.5 Characteristics of the ASMi modem- 52 And Cisco 2811 router

SHDSL modem ASMi-52 Figure 3.4 manufactured by RAD transmits combined data streams (E1, Ethernet or serial) through the SHDSL channel at different transmission rates. The ASMi-52 SHDSL modem uses TC-PAM technology to improve transmission reliability. The ASMi-52 modem uses SHDSL technology with TC PAM-16 linear code, which allows you to increase the range of digital communication lines. They provide data transmission over long distances at speeds up to 2.3 Mbit/s over a single copper pair.

Figure 3.4 modem ASMi-52

The 2811 is an integrated services router that provides all the modern communications needs of small stations.

Can perform the following functions:

access router and local network router;

integrated security solution (variably

anth Security bundle and Voice Security bundle);

Firewall;

Intrusion Prevention System;

encryption and creation of VPN tunnels;

Cisco NAC system and URL filtering;

· The table below shows the maximum capabilities of the Cisco 2811 chassis. Depending on the delivery option (Bunlde) and the installation of additional modules, the characteristics may differ from those shown in Table 3.3.

Table 3.3 Cisco 2811 Chassis Maximum Capabilities

ParameterValuePacket routing: · up to 120,000 packets/sec · up to 61.44 Mbps VPN application performance with built-in encryption accelerator · up to 150 VPN tunnels · 3DES, AES - up to 50 MbpsPerformance in VPN applications with the AIM-VPN/SSL-2 module installed · up to 1500 VPN tunnels · 3DES, AES 140 - Mbps Firewall performance up to 130 Mbps Number of phones in IP PBX CallManager Express or Survivable Remote Site Telephony up to 36 IP phones Number of simultaneous calls on digital channels: up to 80 Number of analog telephone lines: up to 28 FXS or 24 FXO Number of voice mail boxes: up to 120 · Interfaces: Built-in Ethernet interfaces 2 10/100 FastEthernet interfaces Additional Ethernet interfaces: up to 2 additional Ethernet port when installing two HWIC-1FE modules Supports various WAN connections: Requires installation of additional modules WLAN support: Requires installation of additional module HWIC-AP-G-E or HWIC-AP-AG-E or connecting an access point Slots for expansion modules: HWIC/VWIC/ slots WIC/VIC4PVDM slots2AIM slots2NM slots (for NM, NME modules)1

.6 RLSM-10-45 new generation radio station

At the station, according to the project, two radio stations RLSM-10-45 will be installed . RLSM-10-45 Figure 3.5 is a stationary radio station of a new generation, designed to ensure joint operation with the radio communication equipment of the Transport system and the ZhRU complex operated on the railway network.

Figure 3.5 Radio station RLSM-10-45

The radio station after installation will provide:

conducting negotiations and working in data transmission mode in the HF, VHF bands;

independent negotiations using two stationary PS consoles;

connection of two dispatch communication lines with interfaces: analog 4-wire, analog 2-wire, digital E1, digital Ethernet/VoIP;

connection of external TU-TS devices, ADF data transmission equipment;

connecting the PT technological console;

connecting a conversation recorder;

Ethernet local network connection for monitoring and configuration.

Distinctive functional features of the RLSM-10-40 from the RS-46MC are:

the presence of a separate Ethernet port for monitoring and administering the radio station;

extensive possibilities for remote configuration and diagnostics using the automated workplace of the PEGAS control system;

when connecting the workstation via Ethernet, it is possible to work with all radio stations on the network

an accessible way to update software using an automated workstation, which makes it possible to add new functionality and refine existing ones;

the ability to transfer data to a radio channel from external equipment connected via an Ethernet or RS-232 interface;

presence of a digital E1 interface for connecting LDS;

Availability of digital Ethernet/VoIP interface. Ensures readiness for inclusion in a promising IP-OTS network. SIP protocol support (codecs G.711, G.729, G.723). Modern codecs G.729, G.723 allow you to occupy less channel width.

automatic automated control system for the HF range with remote control and monitoring. The adjustment is carried out automatically upon command from the workstation;

It is planned to install it in a radio communication cabinet instead of RS-46MC radio stations.

.7 Network multiplexer SMK-30

For installation and redundancy of DC “YUG” and SPD LP systems, it is planned to use an additional network multiplexer-concentrator SMK-30 with a set of modules. In the main SMK-30 (main) according to the project, it is planned to install modules 1SMA4-4 for the SPD LP system, 6SMTSG - for the DC SOUTH system and 13 SMTS-4 - for communication of meetings. In the reserve SMK-30 (res.), modules 1SMA4-4 are installed for redundancy of the SPD LP system, 2SMA4-4 - output for the RLSM-10-45 VHF radio station, and module 5SMTSG - for redundancy of the DC YUG system.

The SMK-30 network multiplexer-concentrator is designed to operate as part of a digital data transmission network (DSTN). The multiplexer works with E1/PCM-30 channels (PCR), as well as with 64 kbit/s (DC), n x 64 kbit/s channels with various subscriber terminations. SMK-30 allows you to organize communication between remote objects via digital channels (point-to-point and group) 64 kbit/s, n x 64 kbit/s with different endings; via analog channels TC (“point-to-point” and group) with 2 and 4-wire terminations; organize channels for trunk lines (CL) between automatic telephone exchanges.

SMK-30 supports routing function in accordance with IEEE 802.3 Ethernet, IEEE 802.3u Fast Ethernet standards at speeds of 10 and 100 Mbit/s in full-duplex and half-duplex modes. To connect the subscriber device, standard connecting cables are used: 10BASE-T - UTP cable category 3, 4 or 5 for a speed of 10 Mbit/s; 100BASE-T - Category 5 UTP cable for 100 bps speed. b

SMK-30 is used in networks built on the basis of SDH technologies. The multiplexer is designed for operation in networks for various purposes, including networks of OTN and ObTS of Russian railways. 8888 SMK-30 combines almost all railway communication systems and technologies, including: the synchronous digital hierarchy (SDH) transmission system of the STM-1 and STM-4 levels. Digital transmission systems over symmetrical copper cable (DSC DSL), data transmission system for operational and technological purposes (STD-OTN), OTS system, OTS system, meeting communication system (CC), data transmission system with IP protocols (STD IP) and system technical security equipment (TSF). Figure 3.6 shows the capabilities of SMK-30.

Figure 3.6 - Functional diagram of SMK-30

The multiplexer equipment includes:

Network multiplexer-concentrator SMK-30, the number indicates the number of subscriber connectors;

a corresponding set of modules installed in the multiplexer.

Depending on the configuration, the digital data network equipment may also include the following devices:

network administrator workstation,

Digital physical line modem MTsFL-1 with Uko channel,

MCFL-1M digital physical line modem with SHDSL trunk channel,

SHDSL linear path regenerator RLT-1.

The basic multiplexer delivery set includes: a rack (basket), a backplane, a power supply, a system module, a power cable, a set of connectors and documentation. Typical versions of basic kits for ordering are shown in Table 3.4.

If necessary, increasing the number of E1 ports is carried out using the CMPE1-4 module (4 channels in each). Maximum number of output E1 ports for multiplexers:

For execution of 3 - 24 E1 streams,

for versions 4 and 5 - 64 E1 streams.

If it is necessary to output more streams, additional multiplexers are used. All output E1 streams are available for internal use by the multiplexer modules, so there is usually no need to output a large number of E1 streams in the form of external physical ports. The modules can receive nx64 kBit/s and nx2048 kBit/s streams (for example, for organizing high-speed IP networks of routers).

Table 3.4 - Options for basic multiplexer kits

No. Name of Equipment Type E Ports Serviced communication system and equipment Optical SFP slots Level Note 1 Primary multiplexer MUX4SPD-OTN, SS, TSO, SPD IP, DSL0E115 installation places 2 Switching station KS4OTS, ObTS0E115 installation places 3 Primary multiplexer MUX8 SPD-OTN, SS, TSO, SPD IP, DSP DSL0E115 installation places 4 Optical and primary multiplexers in 1 block MUX4-602STM-115 installation places

The power supply unit of the kit has a built-in guaranteed power supply system. When using a power supply, the use of an external uninterruptible source is not required; a maintenance-free 60V battery is directly connected to the multiplexer. The battery capacity is determined based on the required battery life and filling of the multiplexer, usually 7 or 16 Ah.

The optical ports of the multiplexer are SFP slots in the system module into which replaceable laser transceivers with the required parameters are installed. Transceivers can be installed on the fly without turning off the power. All transceivers support digital diagnostics of the optical path. The transceiver is selected in accordance with Table 3.5.

The transceiver type is determined automatically and does not require software configuration. Transceivers of different types can be installed in one system module.

Table 3.5 - Laser optical transceivers for SMK-30

TypeLevelWavelength, nmOutput power, dBMinimum input power at error rate 10 -10, dBMaximum permissible input power at an error rate of 10 -10, dRange (including margin for aging and connections), kmS1.1STM-11310-15… - 8-34 (-36) -80-50 (0-65) L1.1STM-11310-5…0-34 (-36 )-1010-80 (10-90)L1.2STM-11550-5…0-34 (-36)-1020-130 (20-143)S4.1STM-41310-15… - 8-28 (-30) -80-30 (0-48)L4.1STM-41310-3…+2-28 (-30)-810-70 (10-85)L4.2STM-41550-3…+2-28 (-30) -820-110 (20-136)

Transceiver optical connector type - LC. Single-mode optical fiber is used, reception and transmission are carried out over different fibers. The multiplexer can be equipped with the required number of optical patch cords. To order, you only need to indicate the required length and quantity. Characteristics of the supplied patch cord - LC-FC duplex single-mode. The use of optical attenuators is not required over the entire attenuation range.

Multiplexers are equipped with modules with different endings. The list of modules used in the project is shown in Table 3.6.

The SMK-30 multiplexer allows you to install up to 15 modules with

various endings and functions. The maximum number of subscriber channels is 60 for 4-wire channels and 120 for 2-wire. It is possible to organize point-to-point connections and group channels for both analog and digital connections. Supported cross-connect: nx64 kBit/s for E1 streams (up to 32 streams), nx2048 kBit/s and full cross-connect for STM. Synchronization can be carried out from external sources (two separate inputs), from E1 streams, from linear STM paths using a priority scheme. The multiplexer also has two separate sync outputs for synchronizing other equipment.

Table 3.6 - List of SMK-30 multiplexer modules

TypeServed lines Number of channels Note SMA-4-4Analog Four-wire 44-wire channels TCHSMA-2-4Analog two-wire combined 4Analog telephone sets CB/MB, interface with ATS, OTS interfaces, two-wire channel TC 600 Ohm SMTSG-4 Digital 4-wire, 64 kBit/sec, co-directional junction4 ASDC and others. SMTS-4 Digital nx64 kBit/sec, interfaces V.35, RS-232, RS-422, RS-423, RS-4854 Universal serial connections asynchronous and synchronous, point-to-point and group, speed grids 50...234 400, nx64, nx56 kBit/sSMOPS 7 universal ports 7 Security and fire alarm module, active and passive sensors, 7 universal security zones

The technical characteristics of the multiplexer are given in Table 3.7.

Table 3.7 - Technical characteristics of the multiplexer

Characteristic Value Number of E14 channels Maximum number of subscriber modules 15 Maximum number of subscriber channels 60 or 120 when using a multiplexer as a mini-PBX Switching capacity 256 / 512 Switching Arbitrary, any time slots of E1 channels and subscriber modules Conditional height 3 U Maximum weight 9 kg Voltage of the main power supply 220 V ± 30 %Backup power supply voltage45-80 VPower consumption25 -70 W depending on the number of active channels Mean time between complete failures At least 5 years during the service life with an average recovery time of no more than 0.5 hours.

4. Installation and configuration of equipment

The new equipment will be installed in the communications room at the EC post at station C and is shown in Figure 4.1. The numbers in the figure show the location of the following equipment. In the communication room:

Cabinet with newly installed equipment (BG-30, Cisco 2811, GPL-12-200 batteries 4 pieces)

Cabinet "Ob-128TS" (SMS-150S, NEC, SPSS-128, SMK-30 UPS)

Radio communication cabinet (RLSM-10-45 VHF, RLSM-10-45 KV, RI-1M, UPS)

TA OTS DTP-16D

Optical cross-connector SHCHOR-24P

Compressor "Sukhovey"

TSS cabinet (RS TSS-M, URSS, SMK-30 batteries 5 pieces)

After reconstruction, the following equipment will be installed in the chipboard room and is shown in Figure 4.1:

Remote control RLSM-10-45 KV

Remote control RLSM-10-45 VHF

AWS "Vector"

Figure 4.1 Equipment layout after reconstruction

.1 Installation of multiplexer BG-30

The multiplexer ensures the transmission of virtual containers over optical fiber. A cross-commutation matrix is ​​used to process containers. High-speed optical interfaces enter the BG-30 from two directions. For I/O of lower-speed streams, interface modules with E1 and Ethernet interfaces are used. Data coming from modules with E1 Ethernet interfaces is converted into virtual containers, then multiplexed into an STM-16 channel and transmitted via an optical interface.

At the initial stage of installing the BG-30 multiplexer, the location where the equipment will be located is selected. For this purpose, an additional cabinet is installed. BG-30 is installed in a 19 rack, the working position is horizontal. Installed in a standard cabinet located in the communication room shown in Figure 4.1 under number 1.

After installing the BG-30 multiplexer, the power supply is connected. Power is supplied from an alternating current source with a voltage of 220V or it is possible to connect from a source with a constant voltage from + 48V to - 60V, if powered from a constant current source it is necessary to use an INF-20B surge protector, but the project uses an alternating current source.

The following circuits are connected to the BG-30 multiplexer through external connectors: optical reception and transmission, reception and transmission of E1 and Ethernet signals, power supply. The fiber-optic cable is inserted into the station into the optical cross-connect SHOR - 24P, which is designed for placement and fastening of cables during installation. From the optical crossover, it is supplied via optics to the multiplexer and occupies an intermediate position, transmitting the aggregate data stream in the line. Optical fibers are connected according to the inscriptions on the panel of the optical termination module: RX reception, TX transmission.

The multiplexer uses input/output ports to input and output data onto the line.

The E1 circuit is installed using a multi-core D-Sub 25 Pin cable. On one side there is a plug on the other side there is a free end for connecting to the cross. The input/output multiplexer BG-30 Figure 4.2 is installed in the communication line gap to output several channels from the general stream.

Figure 4.2 BG-30 connection diagram

The BG-30 multiplexer is connected via SDH to the optical interface. SDH (Synchronous Digital Hierarchy) - synchronous digital hierarchy is based on time synchronization of the transmitting and receiving devices. The SDH and PDH hierarchies interact through procedures for multiplexing and demultiplexing PDH streams into SDH systems in the BG-30 multiplexer. The SDH system performs synchronous multiplexing/demultiplexing, which allows direct access to PDH channels. The SDH system provides standard levels of information structures, that is, a set of standard rates. The basic speed level is STM-1 at 4,6,64 respectively; 622Mbit\s (STM-4) and 2.5Gbit\s (STM-16). The BG-30 is a multiplexer of STM-1 - STM-16 I/O topologies. All information in the SDH system is transmitted in containers.

A container represents structured data transferred within a system. Over the network, STM-1 containers are transmitted via the SDH system at different levels.

Appendix B shows the connection of the BG-30 multiplexer to the equipment.

The BG-30 multiplexer outputs 21 E1 streams using PDH (Plesiochronous Digital Hierarchy) technology. Plesiochronous digital hierarchy is a digital method of data and voice transmission based on time division of the channel and signal provision technology using pulse code modulation. In PDH technology, the signal of the main digital channel (BCC) is used as an input, and a data stream with speeds n is formed at the output × 64 kbps. To the group of BCCs carrying the payload, service groups of bits are added, necessary for the implementation of synchronization and phasing procedures, signaling, and error control, as a result of which the group takes the form of a cycle.

On one side there is a plug on the other side there is a free end that connects to the cross. According to the diagram in Figure 4, 17 E1 threads will be involved. The equipment is connected via twisted pair cable using the G.703 interface.

The G.703 interface serves networks with a PDH and SDH hierarchy. It was originally developed for pulse code modulation systems. G.703 can operate at data rates of 64 Kbps, 1544. It is also possible to operate at 155.52 Mbps. Twisted pair (Z=100-120 Ohm) or coaxial cable (75 Ohm), pulse amplitude 1-3V can be used as a physical transmission channel.

At a speed of 64 Kbit/s, three types of signals are transmitted through the interface: information (64 Kbit/s) and two synchronizing clocks 64 Kbit/s and 8 Kbit/s.

Distribution of streams from the multiplexer:

Pins 5 and 6 will be connected to the SPD-ITC node. In this unit, the automated workplace DSP, TVK, and “Vector” programs are installed, which are created to optimize work and improve working conditions for workers, as well as with their help to configure equipment remotely.

Pins 7 and 8 are connected to the router to the E1 stream input port of Cisco 2811. Designed for remote control and regulation of RMU-4 devices and radio stations. Also, via Cisco 2811, MDKs are connected, which are designed to monitor the power status (220V sag, lack of power PN-48-60\24, general power failure of the recorder, etc.)

and output 12 is connected via an optical line from BG-30 to SMK-30. The BG-30 multiplexer is the main one in case of failure and is backed up by the SMS-150C multiplexer. SMK-30 is equipped with certain modules depending on its purpose.

and output 14 will be connected via an optical line to the backup multiplexer SMK-30 and in case of failure of the main one, the switch to the backup one will automatically occur.

Outputs 15 and 16 are connected to the ASMI52 modem and with its help data is transmitted to the EChE Tur and PPS substation.

19 and 20 ports data transmission and control of input/output multiplexers SMS-150C and BG-30.

.2 Setting up the BG-30 multiplexer

Setting up means software configuration of the multiplexer to switch digital streams of different speeds, set channel labels, and establish protective channels. Everything necessary for configuring the BG-30 is done only using a computer with installed software. The software control and monitoring system is designed to monitor the status of all multiplexer joints: optical, E1, Ethernet, operational control BG-30.

To work with the equipment, you must initially set the IP address of the multiplexer. The multiplexer IP address can only be changed if a computer is connected to the Ethernet port. The specified IP addresses of the blocks are entered into the network map of the monitoring program.

To get started, you need to set the multiplexer's IP address:

To do this, you need to configure the Ethernet connection properties on your computer. Start - Settings - network connections - local network connection - properties. Internet Protocol (TCP\IP) - properties. The default IP address for the connection is 192.168.1.1. Then the subnet mask is assigned 255.0.0.0 - OK

connect the computer’s Ethernet port to the “NM” connector of the multiplexer using a crossover Ethernet patch cord.

run the command line on your computer: Start => Run => type cmd => ok. In the window that appears, type telnet Figure 4.3. Next, type open 192.192.4.3 the current IP address of the multiplexer and press Enter.

Figure 4.3 Command Line

Enter the username Admin and press Enter. Enter the default password admin and press Enter Figure 4.4.

Figure 4.4 Command line input login

The message “User “admin” logged in” appears, meaning that the connection was successful (Figure 4.5). And if the message Password error or user is inexistent appears, it means the username and password are entered incorrectly.

Figure 4.5 Command line successful connection

Enter the required multiplexer address, 192.162.4. 3 press enter Figure 4.6.

Figure 4.6 Command line entering multiplexer address

The next input field is the subnet mask. 255.255.255. - press Enter. MAC address does not change. The next input field is the default gateway. Enter Y press Enter. The gateway address is 192.168.1.1, press Enter, Figure 4.7. A confirmation line for the operation appears.

Figure 4.7 Command line entering subnet mask, default gateway

After entering a new address, the connection will be lost. To check the connection settings, you need to start the connection again with the address 192.168.1.103 (open 168.1.103 name admin password admin). Type the getinfo command and press Enter. Information about the properties of the multiplexer appears (Figure 4.8).

Figure 4.8 Command line multiplexer properties information

The remaining settings are made using software, remotely. According to the technological map, you can configure the equipment synchronization; for this you need to:

1. Connect to the EMS-APT server via GoGlobal to do this:

Launch GoGlobal and select Server Address => in the window that appears [email protected]=>Transport:TCP/IP

In the window select NMS Client => NMS Client => Start NMS Client

Enter personal data login and password

On the SDH slot select Tools - Timing Map

The synchronization subnet topology opens. The quality of the synchronization signal corresponds to the color of the links between network elements. Visually, by the color of the links, evaluate possible deviations from the correct level of synchronization signal quality. If necessary, you can go to the synchronization block to view its configuration and adjustments.

In the network element shelf overview window, select Control and Phyical Object > TMU in the object village, select the Timing Settings synchronization settings tab under the Configuration operating mode.

For each clock priority level, the correct selection of external reference clock sources is verified.

Changes are made as necessary and the Apply button is clicked to send the external reference sources to the network element.

The software also allows you to analyze the condition of the equipment using the online monitoring system, which helps to find the cause of the malfunction:

1. Connect to the LS(LSc1) client via GjGlobal to do this:

launch GoGlobal and select Server Address => in the window that appears [email protected]=>Transport:TCP/IP

Click the Connect button and enter Password;

Open the program by launching the ECI NM shortcut;

In the window select NMS Client => NMS Client => Start NMS Client

Enter your personal data login and password.

We open the Current alarms window, analyze existing alarms, and apply measures to eliminate them.

Accidents are classified according to the following severity levels

If there are equipment alarms in the list of current alarms, the availability and serviceability of equipment on the network is checked. Depending on the current state, the BG-30 item icon will be colored accordingly

To eliminate faults in the BG-30 element, you can enter it directly from the LS program. The tree in Figure 4.9 of the multiplexer displays the boards included in its composition. If a module or channel malfunctions, the object icon will have a sign characterizing the degree of failure

Figure 4.9 Object tree

If an alarm signal is detected on the image of the multiplexer (module), find out the cause and take corrective action.

4.3 Multiplexer installation SMK-30

Installation of the SMK-30 multiplexer begins at the installation site. According to the project, it is planned to install the backup multiplexer in the TSS cabinet, whenever there is free space there. Installed in rack 19, horizontal working position. SMK-30 has a block design (Figure 4.10), consisting of functional modules: power supply and display module, system module, subscriber modules.

Figure 4.10 Multiplexer SMK-30 front panel

The modules are installed in a crate with 17 seats. The leftmost place (slot No. 0) is intended for installing a power and display module, the far right (slot No. 16) is for installing a system module. In the remaining 15 places (slot No. 1 - No. 15), we install the necessary modules in random order (Figure 4.11).

Figure 4.11 Reverse side of SMK-30

The front door of the SMK-30 has a window for the display panel. When closed, an LCD display, LED indicators of general status, E1 status and synchronization, and a button to turn off the audible alarm / reset the alarm are available. When the door is open, access to menu buttons, power switch, general module status and channel status LEDs is provided.

The main multiplexer and the previously installed SMK-30 will be supplemented with modules. The 1SMA4-4 board is installed in the first installation location. The 2SMA4-4 module is installed at the 2nd installation location. The 5SMTSG-4 module is installed at the 5th installation location. Boards for 1СМА4-4, 2СМА4-4, 5СМЦГ-4 are installed in the backup multiplexer, Figure 4.12.

Figure 4.12 SMK-30 installed modules

The connection of optical fiber from the BG-30 multiplexer from ports 13 and 14 is supplied to front panel ports 1 and 2. From the 1SMA4-4 board - output 1-1 - over twisted pair, the LP SPD is redundant. From the 2SMA4-4 board, output 2-1, the RLSM-10-45 VHF radio station is connected via twisted pair. From the 5SMTSG-4 board, output 5-1 - DC SOUTH is reserved via twisted pair.

The 1SMA4-4 board is installed in the first seat. The SMA4-4 board is designed to organize four analog channels 600 Ohm PM with four wire terminations. The board allows you to organize communication in point-to-point mode and in group mode. Board 5SMTSG-4 Designed to organize four G.703 channels, used when connecting the digital system DC YUG. Power supply is provided from a guaranteed alternating current supply voltage of 220V +\ - 30% with a frequency of 50 Hz or connecting an external source of direct voltage from - 35 to -90 V. The main power supply for the multiplexer will be a 220V network, and the backup power source will be a maintenance-free battery -60V.

.4 General multiplexer setup SMK-30

Configuration, control, monitoring and administration of SMK-30 are carried out remotely using the administrator's automated workstation (AWS) program. SMK-30 comes with an ADMIN account without a password. The SMK-30 workstation can be connected via the RS-232 interface or via the Ethernet interface.

After connecting the PC to SMK-30, you need to launch the Network Administrator program. After starting the program, a dialog box will appear on the screen. In the Registration tab of this window, you must enter the user name - ADMIN, the password remains blank (Figure 4.13).

Figure 4.13 Dialog box “Configuring workstation connection”

In the Interface tab, Figure 4.14, in the appropriate fields, you must indicate the type of interface through which the connection was made, its settings, as well as the subnet number and the device address in the subnet for the Network Administrator program.

Figure 4.14 - Dialog box “Configuring workstation connection” Interface tab

After clicking the OK button, the main window of the automated computer will open, the general view of which is shown in Figure 4.15.

Figure 4.15 - General view of the Network Administrator program window

First of all, administrator accounts that have access to this station, as well as their rights, are configured. The administrator account ADMIN is changed for security purposes.

Next, you need to make network settings, which consist of setting the station name, specifying the subnet number and network address. So, in Figure 4.17 SMK-30 is given the name station C, it belongs to the zero subnet and has a network address equal to one.

In order for SMK-30 stations to exchange messages, and also for the administrator’s workstation to be able to monitor and configure SMK-30 stations that are not directly connected, it is necessary to configure network routes.

You also need to configure directions and routes. A route defines one or more directions along which a call is made. One direction is the main one; when called, this direction is analyzed for availability. If the main direction is unavailable, the call is transferred to additional directions in order. When connecting the required module, it is necessary to configure it.

The SMA4-4 module is the main thing when configuring the choice of line type (NO, DATS, Radio station, outgoing 2 of 11, incoming 2 of 11, direct subscriber unit, switch, ADASE) for an example of tuning, I’ll take the tuning of radio stations, the rest of the settings are the same. Settings are issued early and are set either remotely or through a special connector at the station.

When connecting the radio station RLSM-10-45, the following settings are set, Figure 4.16.

Figure 4.16 Configuring the SMA4-4 module

The first line sets one of the types of radio station RS46M or RLSM10. The second line sets the gain level when transmitting to the line. Available values ​​from minus 30 to plus 30 dB. On line 3, the gain level in dB when receiving from the line, values ​​from minus 30 to plus 20 dB. On the 4th line, the level of control signals, values ​​from -29 to 0 dB.

5 line time of involuntary exercises values ​​from 0 to 250 s. 6 line duration of SIP, SKP parcels values ​​from 96 to 496 ms. 7th line duration of Sper, Spr messages from 48 to 496 ms. Line 8 automatically issues a Locomotive call signal; the value is allowed or prohibited. 9 line duration of sending a call to the PC values ​​from 1000 to 2000 ms. 10 line detector bandwidth values ​​from 1 to 5%.

The basic software settings of the multiplexer are shown in Figure 4.17:

Figure 4.17 Appearance of the multiplexer settings window

Network name - any user-friendly designation of a given multiplexer within a subnetwork, consisting of Russian / English letters, numbers up to 19 characters inclusive, in the project the network name Station C is assigned:

The number of the subnet that this multiplexer is part of. Can take values ​​from 0 to 63. This multiplexer is located in the first subnet;

Address - the unique network address of the multiplexer. Can take values ​​from 0 to 31, in the diploma project it takes 26;

The number of subnets included in a single global network of multiplexers. Can take values ​​from 0 to 63. In the settings of this multiplexer, the value is 5.

Setting up multiplexer timing

Can be synchronized from source:

Synchronization from one of four E1 streams. It is used when connecting several multiplexers into a single network to synchronize all multiplexers in the network from the same source.

The priority system takes values ​​from 0 to 5. The highest priority is 0, the lowest is 5. If during operation synchronization from a source with priority 0 becomes impossible, the multiplexer will switch to a synchronization source with priority 1, etc. If none of the available synchronization sources is selected, the multiplexer will switch to the internal source (AUTO mode) Figure 4.18.

Figure 4.18 Appearance of the synchronization settings window

In the multiplexer settings there is a tab “Ring 1” and “Ring 2” (Figure 4.19) for setting up rings. The following ring settings are available.

1. Ring control can be turned on/off - when the position is on, the state of the ring is checked: the integrity of the ring and the search for the main station in the ring.

Polling period (ms) - after this time interval (milliseconds) the integrity of the ring will be checked.

The number of periods for determining the gap is the number of periods during which the integrity of the ring is determined.

Logical break flow - can take the values ​​first\second, for ring No. 1 this means a logical break along flows 1E1\2E1, respectively, for ring No. 2 this means a logical break along flows 3E1\4E1, respectively.

Figure 4.19 Setting up multiplexer ring No. 1

Setting up E1 streams Figure 4.20:

Figure 4.20 Appearance of the E1 stream settings window

The following settings are available to the user:

Reception\Transmission - setting enabled. This setting is used to remotely disable/enable the E1 stream transmitter and receiver.

Long line mode - enabled. If this mode is turned off, then the maximum signal attenuation is 10 dB. In this mode, the balancing circuit in the E1 controller is disabled and signal level measurement is not allowed.

HDLC controller time slot - the number of the time slot through which service information is exchanged between network devices.

Remote loop. The remote loop diagram is shown in Figure 4.21. In this case, the loop closes the reception of E1 and the transmission of E1 from the communication line of the E1 controller. The receiving signal of the E1 stream enters directly into the transmission line without the participation of the internal circuits of the controller. This mode can be used to check the quality of transmission over a communication line.

Figure 4.21 Scheme of the remote PSP loop

.5 Installing the ASMi-52 modem

The modem is installed in the communication room and connected from the crossover with a twisted pair cable. Installation is carried out in the same cabinet with the BG-30 multiplexer.

The ASMi-52 modem uses SHDSL technology with TC PAM-16 linear code, which allows you to increase the range of digital communication lines. Modem

ensures data transmission to the substation EChE Trg and PPS at speeds

up to 2.3 Mbit/s over one copper pair.

The modem has custom ports E1, V.35, 10\100 BaseT LAN with

router. Two ports multiplex V.35\10\100Base TLAN data and E1 traffic via SHDLS. Automatic configuration sets up the device. (Symmetric High Speed ​​Digital Subscriber Line) - a symmetrical high-speed digital subscriber line is aimed primarily at providing guaranteed quality of service at a given speed and range of data transmission.

To organize access via SHDSL, a dedicated line (physical two-wire line) is used at the station. The access speed when connecting via SHDSL is determined by the length of a particular communication line.

SHDSL technology provides symmetrical traffic over one pair in the speed range: from 192 Kbit/s to 2.3 Mbit/s, and over a double pair - from 384 Kbit/s to 4.6 Mbit/s; the project uses one pair.

The advantage of SHDSL technology is the ability to use already existing (laid and actually working) copper pairs of wires for subscriber lines, Figure 4.22.

Figure 4.22 Schematic connection of the ASMI-52 modem

The ASMi-52 modem transmits combined data streams (E1, Ethernet) via an SHDSL channel at different transmission rates. The ASMi-52 SHDSL modem uses TC-PAM technology to improve transmission reliability, allowing it to serve more users at higher data rates over longer distances.

.6 Setting up the ASMI-52 modem.

The modem is configured using the OTS Network Administrator, ObTS program. The modem appears in the list of devices as a separate device, and configuration is performed through the context menu.

To assign a name to the modem, specify the subnet number and network address, select Settings - Network settings in the context menu. The dialog box Figure 4.23 will appear.

Figure 4.23 Device network settings

After entering the required settings, you must name the Apply button. To close the window, click the Exit button.

To configure an SHDSL line, you must select the desired stream and select Settings in the stream’s context menu. The dialog box Figure 4.24 will appear.

Figure 4.24 Setting up an SHDSL channel

Options available in the dialog:

Mode. Defines the operating mode of the ASMI52 SHDLS modem. When setting up a connection between SHDSL modems, one device must be the master (Line Termination Unit), the other devices must be slaves (Network Termination Unit). Synchronization is passed from the master to the slave.

Protocol type. Allows you to select the type of EDSS protocol used in the exchange (network and user)

Minimum and maximum speed. One of two options is used. The first option is a hard speed setting on the near side (in relation to the administrator) with automatic selection on the far side. The second option is to set a range of possible speeds on the near side with automatic selection on the far side.

Level reduction mode. Options: forced, automatic. Reduction of the transmission level relative to the nominal +14.5 dBm.

Attenuation of LTU and NTU transmission levels. Sets the transmit dB reduction values ​​for the forced reduction mode. Adjustable from 0 to 31 dB. The setting can be used to reduce and eliminate the mutual electromagnetic influence of high-frequency systems operating in the same cable. This parameter is only available for the link in LTU mode, but is effective on both transmitting sides.

Line measurement mode. Allows or prohibits measurements when establishing a connection via an SHDSL channel.

Line measurement time. Adjustable from 50 to 3150 ms. The parameter specifies the time during which the line is measured for each possible transmission rate. The recommended value is at least 10 ms. The total connection setup time depends on the line measurement time.

SNRM threshold (measurement mode and operating mode). The permissible signal to noise ratio in dB is set. Adjustable from 0 to 63 dB. A signal to noise ratio of 20 dB corresponds to a bit error level of 10 -7.At the line measurement stage: if the measured SNR value for a given speed is less than a specified threshold, this speed is not considered possible for establishing a connection. When the connection is established (operating mode): if the measured SNR value becomes less than the specified threshold, an SNR alarm is set and an alarm message is displayed in the administrator's workstation. The recommended value is at least 20 dB.

Signal attenuation threshold. Sets the acceptable attenuation of the SHDSL line signal. Adjustable from 0 to 30 dB. If the measured attenuation value becomes greater than the specified threshold, a LOSS alarm is set and an alarm message is displayed in the administrator's workstation. The value is set to 2-5 dB more than the measured attenuation for a given communication line.

Time slot alarm. This parameter specifies the time slot used for EDSS signaling.

SHDSL line monitoring and control.

To monitor an SHDSL line, you must select the desired stream and select “Monitoring” in the stream’s context menu. A dialog box will appear as shown in Figure 4.25.

Figure 4.25 SHDSL Channel Monitoring

Connection setup procedure. The initial state is “No connection”. In this state, SHDSL modems exchange initialization signals. After determining the presence of a physical connection, the modem goes into the “Line Measurement” state. The equipment measures the line at speeds that are common to them. For each speed, the measurement is carried out for a specified time. The more time, the more accurate the result. The result of the measurement is the calculated signal to noise ratio in dB. SNR 20 dB corresponds to a bit error level of no more than 10 -7. After completing the measurement to establish a connection, the maximum speed is selected for which the measured SNR value is not less than the specified signal-to-noise ratio threshold. The signal level when measuring a line, as well as for the operating mode, is set by the “Reduce transmission level” setting. After the measurement, the modem goes into the “Communication Establishment” state, in which the operating transmission speed and synchronization are established. After this, the “Connection established” state is established and the channel operates in normal mode.

In the “SHDSL Monitoring” tab, Figure 4.25, parameters are available;

Communication status. Enables a line status bar that displays a text description of the current status: "No Link, Line Measurement, Link Established, or Link Established." The indicator is a visual representation of the connection status. The indicator is red in the “No connection” state, yellow in the “Line measurement” and “Communication establishment” states, green in the “Communication established” state;

SNR. Indicator of exceeding a specified signal-to-noise ratio threshold. Lights up red when the measured signal to noise ratio is below the threshold specified in the setting. The indicator is green when the SNR value is normal;

LOSS. Indicator of exceeding a specified signal attenuation threshold. The indicator is red when the measured attenuation is above the threshold specified in the setup. The indicator is green when attenuation is normal.

Signal to noise ratio. International abbreviation SNR (SIGNAL-TO-Noise Ratio). Shows the measured SNR value at the current time in dB. SNR 20 dB corresponds to a bit error level of no more than 10 -7.

Signal attenuation. Shows the measured attenuation value of the received signal in the communication link in dB. The permissible attenuation at which communication is possible is about 25-30 dB.

Downgrade. Shows the current reduction in the transmit signal level in dB.

Transfer speed. Shows the currently set data rate in time slots.

ES (Errored Second) counter. A second with an error. Shows the number of 1-second time intervals during which 1 or more CRC errors or 1 more sync word errors occurred.

SES (Severely Errored Second) counter. A second struck by errors. Shows the number of 1-second time intervals during which at least 50 CRC errors or more sync word errors occurred.

LOSWS (Loss of Sync Word Second) counter. Second with synchronization error. Shows the number of 1-second time intervals during which 1 or more syncword errors occurred.

Slippage on reception and transmission. Shows the number of slippage - synchronization errors with accompanying insertion / deletion of characters;

UAS (UnAvailable Second) counter. Seconds of line unavailability. Shows the number of 1-second time intervals during which the SHDSL line is in an unavailable state. The line becomes unavailable after 10 consecutive error-stricken seconds (SES). These 10 seconds are included in the unready period. The line becomes ready after 10 consecutive seconds without being affected by errors (per SES).

The “Reset Count” button is used to reset the counters. After the connection is established, the CRC, ES, SES, LOSWS counters are automatically reset to zero.

The “SNR and SHDSL Measurement” tab, Figure 4.26, displays the measured SNR values ​​for the speeds possible to establish a connection. The measurement result is not available for those speeds that are not common to modems for which the measured SNR value is below the threshold specified in the setting.

Figure 4.26 “SNR and SHDSL Measurement” tab

5. Reliability

.1 Basic concepts of reliability

Reliability is the property of an object to perform specified functions, maintaining over time the values ​​of established operational indicators within specified limits corresponding to specified modes and conditions of use, maintenance, repairs, storage and transportation.

The SMK-30 multiplexer can be in two states, namely operational or inoperative.

Operability is the state of an object in which it is capable of performing specified functions with the parameters established by the requirements of technical documentation.

An event that disrupts performance is called a failure. An event consisting of a transition from a primary operational state to a secondary one is called damage (minor failure, defect).

Based on the nature of their occurrence, it is customary to distinguish between sudden failures, consisting of a sharp, almost instantaneous change in a defining parameter, and gradual failures, occurring due to a slow, gradual change in this parameter.

Reliability indicators are quantitative characteristics of one or more properties that make up the reliability of elements and systems.

Reliability indicators must satisfy the following conditions:

best reflect the effect of normal system operation and the consequences of its reliability;

be able to be calculated taking into account the available initial data;

relatively easy to determine based on statistics;

be simple, have a clear mathematical and physical meaning.

One of the central provisions of reliability theory is that it considers failures as random events. The time interval from the moment the element (system) is turned on until its first failure is a random variable called “failure-free operation time.” The cumulative distribution function of this random variable, which is (by definition) the probability that the failure-free operation time will be less than t, is denoted by Q(t) and has the meaning of the probability of failure in the interval 0…t. The probability of the opposite event—failure-free operation during this interval—is equal to

P(t) = 1 - Q(t),

Q(t) - probability of failure.

A measure of the reliability of elements and systems is the failure rate λ( t), which is the conditional probability density of failure at time t, provided that there were no failures before this moment. Between functions λ( t) and P(t) there is a relationship

,

where P(t) is the probability of failure-free operation;

λ( T) - failure rate.

During normal operation (after running-in, but before physical wear sets in), the failure rate is approximately constant λ( t ) ≈ λ. In this case

P(t) = e- λt.

Thus, a constant failure rate characteristic of a period of normal operation corresponds to an exponential decrease in the probability of failure-free operation over time.

The average time between failures (mean time between failures) is found as the mathematical expectation of the random variable “time between failures”

.

Consequently, the average time between failures during normal operation is inversely proportional to the failure rate

Let us evaluate the reliability of a complex system consisting of many different types of elements. Let P1 (t), P2 (t),…, Pn(t) be the probabilities of failure-free operation of each element in the time interval 0…t, n is the number of elements in the complex. If failures of individual elements occur independently, and the failure of at least one element leads to failure of the entire complex (this type of connection of elements in reliability theory is called sequential), then the probability of failure-free operation of the complex as a whole is equal to the product of the probabilities of failure-free operation of its individual elements

Where Λ complex = λ i - failure rate of the complex;

λ i - failure rate of the i -th element.

Average uptime of the complex

.

The main characteristics of the reliability of restored elements and systems include the availability factor. Availability coefficient Kg(t) is the probability of the complex being operational at time t

,

where tВ is the average recovery time of the element (system), h.

5.2 Calculation of the probability of failure-free operation of the SMK-30 multiplexer

The average service life before decommissioning of the multiplexer must be at least 20 years. During the service life of the station, the supplier guarantees compliance of the product parameters with the technical specifications when using a set of spare equipment and instruments and subject to the consumer’s compliance with the operating, transportation and storage conditions established by the technical specifications.

Each of the components of the complex (except for cables and cabinets) must have the following reliability indicators:

Mean time between failures tav = 10000 h;

average service life before write-off (full) - at least 20 years;

The accepted test duration for each object is t = 2920 hours (we choose based on the fact that the system is operated for 8 hours every day);

Maximum recovery duration tв = 10 min;

acceptance number of non-recoveries St = 0 (non-recoveries are not allowed).

Complex failure rate Λ com, will be equal

Λ com .

With an exponential law of distribution of recovery time, the recovery intensity µв

Where μ B - recovery intensity;

tВ - average recovery time of the element, tВ=1.3 s.

Substituting numerical values ​​into the formula, we find the recovery intensity

The probability of failure-free operation for a given period of time is found using the formula

Pcomplex(t) = e Λ com·t.

Substituting numerical values ​​into the formula, we find the probability of failure-free operation for a given period of time

Pcomplex(t) = e - 0.29 = 0.75.

The probability of failure of the complex Q(t) is found by the formula

Q(t) = 1 - P(t).

Substituting numerical values ​​into the formula, we find the probability of failure of the complex

Q(t) = 1 - 0.75 = 0.25.

Substituting the obtained numerical values ​​into formula (5.2) we find the availability factor of the complex

To ensure the reliability of the OTS equipment, it is necessary that the availability factor be at least 0.99. This condition is met for the SMK-30 multiplexer.

The widespread introduction of digital transmission systems using fiber-optic cable and the ability to automatically restore the functioning of the network even in the event of failure of its elements ensure high reliability of the functioning of the system as a whole.

Conclusion

At station C of the South Ural Railway, the first stage of reorganization of the communication network was carried out on the basis of modern Broad Gate (BG) equipment produced by ECI Telecom, which makes it possible to provide new

capabilities for end users (Ethernet, monitoring the train environment, status of communication equipment, etc.).

The thesis project examines the reorganization of the communication network at station C. The installation of new communication equipment at this station is economically feasible.

The first section presents the characteristics, description and operating principle of the equipment installed before the reorganization and also shows the placement of the equipment in the communications room and the connection diagram of the communications equipment.

The second section provides the rationale for installing new equipment. The emergence of new systems for monitoring the state of traffic of DC “YUG” trains, SPD LP presupposes the installation of new equipment.

In the third section, equipment for reorganization is selected. For the primary communication network, a BG-30 input/output multiplexer was installed, to enable the new dispatch control system of the DC “YUG”, an SMTSG4 module was additionally installed in the SMK-30 multiplexer, and a backup module was installed to back up the main SMK-30.

In the fourth section, the equipment is installed and configured. The equipment was configured using the administrator's workstation software

The section “Life Safety” discusses organizational and technical measures to protect personnel from exposure to electric current. An examination of the workplace was also carried out.

In the economic section, an economic assessment of the reorganization of the communication network was made. The economic efficiency of the project was calculated. The payback period of the project is 0.71 years.

Reorganization of the communication network will increase the capacity of the communication channel, as well as the reliability and reliability of communication systems, and will increase the efficiency of managing the transportation process.

List of sources used

1.Vinogradov V.V., Komov V.K. Fiber-optic communication lines. - M.: Zheldorizdat, 2002. - 278c.

2.Dmitrieva S.A. Slepova N.N. Fiber optic technology: history, achievements, prospects / etc. - M.: Transport, 2000 - 608 p.

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4.Instructions for using the SSPS-128 converter and NEAX7400 ICS M100MX switching station. - Chernigolovka.: - EZAN. - 217 p.

5.Ananyev D.V., Kuznetsov A.V. New service technologies based on SMK-30. Popular scientific production and technical magazine Automation, communications, computer science. - M., 2008. No. 5 - 27 p.

6.Olifer B.G., Olifer N.A. Computer networks. Principles, technologies, protocols: Textbook for universities. - St. Petersburg: Peter, 2004. - 864 p.

7.Shaitanov K.L., Karitan K.A. Equipment SMK-30. Methodical manual. - Khabarovsk, 2013. -47 p.

8.Technological maps for the maintenance of ECI BG-30 multiplexers. JSC "Russian Railways" Branch communication station. 2014

9.Operating manual SMK-30. - M.: NPL "PULSAR", 2005.

10.Blinder, I.D. Digital operational and technological communication of railway transport in Russia: illustrated educational manual / I.D. Blinder. - M.: Route, 2005. - 55 p.

11.Lebedinsky A.K. Telephone switching systems: a textbook for technical schools and colleges of railway transport - M.: Route, 2003. - 496 p.

.Order of the Ministry of Health of the SR No. 342 N dated April 26, 2012 “On approval of the procedure for certification of workplaces according to working conditions

13.Annenkova K.I., Cherepanova L.A. Feasibility study of the effectiveness of new equipment, technologies of automation and communication devices, - Yekaterinburg, 2011 - 145 p.

14.Network administrator OTS, ObTS. User's Guide. - Penza, Pulsar-Telecom, 2013

.Kashina S.G., Sharafutdinov D.K. Electrical safety. Protective grounding devices for electrical installations. Kazan 2012 - 137 p.

.Kuznetsov K.B. Life safety. Part 2. - M 2006 - 536 p.

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Currently, the demands of individual and business users on the throughput of metro access networks are increasing, driven by the need to support services that work with regular, voice and video data. Although the BG-20 platform is very compact, it provides access traffic aggregation for STM-1/4 interfaces in point-to-point networks as well as in multi-ring networks. The BG-20 receives and transmits PDH, SDH and Fast Ethernet traffic at local points of presence.

Application in cellular networks
As the cellular market continues to grow, operators must deal with ever-increasing traffic volumes, increasing bandwidth requirements affecting network topologies, and the need to migrate to new technologies (from GSM to GPRS to 3G). All these changes require the use of flexible and scalable optical infrastructure in remote access networks.
The BG-20 platform is an excellent choice for building such networks, thanks to the following features:

• Compact and reliable, allowing this platform to be installed both indoors and outdoors, in harsh environmental conditions.
• Aggregation of data and TDM traffic for a common infrastructure.
• Supports ring, mesh, and point-to-point topologies. Ability to upgrade STM-1 interfaces to STM-4 with minimal impact on traffic.
• High flexibility and low price, increasing the cost-effectiveness of the u1089 network.
• Efficient processing of modern data services (migration to WLAN and IP) provided by cellular operators.
• The DXC 1/0 crossover device and low-speed PCM interfaces enable remote control and monitoring of various types of cellular base stations and base station controllers, eliminating the need for conversion units and reducing capital and operating costs.

The BG-20 platform is designed to meet the growing needs of modern networks, such as reducing the cost of operating city-level systems or cellular systems. The BG-20 platform's ability to meet existing network needs and enable network evolution allows BG-20 to be used as a core element in creating highly competitive solutions and enables operators to cope with unpredictable load growth without having to restructure the network.

The cabinet is equipped with the following devices:

a)RAP-BG is a distribution cabinet with the ability to input power from two sources (SOURCEA, SOURCEB). It switches the secondary voltage of 48 V;

b) MiniPack KGP converts the primary voltage of 220 V into a secondary 48 V. The power of the KGP is determined by a set of MiniPack blocks. There are two such blocks installed on the site, the design of the CGP provides for the installation of four;

c) the SmartPack module, also part of the CGP, controls and monitors the status of the CGP, as well as the parameters of the 220 V input voltage. It is connected to the SPD ESMA network via an Ethernet interface;

d) Artemis optical spectral multiplexing equipment. Implements DWDM and CWDM technology. It does not have any electrical components and therefore does not require power. With its help, several optical signals separated by wavelength can be transmitted in one FOCL fiber;

e) the SDHBG-20 multiplexer performs multiplexing, demultiplexing operations, and also converts the electrical signal into light and vice versa. The BG-20 multiplexer is capable of working with 21 E1 streams, in addition, it has 6 Ethernet ports, which are also used for data transmission. BG-20 and BG-30 provide two power supplies of 48 V each, in addition, BG-30 provides for connecting any alarm circuits to it, for example, the central monitoring station of the fire alarm system (central monitoring panel for fire alarms). BG-20 is capable of not only working with alarm circuits, transmitting any events to ECMA, but also controlling any devices using Alarms OUT. One BG-20 multiplexer provides 4 Alarms IN inputs and four Alarms OUT outputs.

The cabinet also houses batteries to ensure uninterrupted power supply.

Figure 3 – CWDM cabinet configuration

3 Characteristics of communication devices of other workshops
Due to optimization, the hub and combined RVB were combined into one RVB 335, thus, the equipment of the other workshop is distinguished by the presence of a central workshop, Definity automatic telephone exchange and SMK-30 as a multiplexer.

3.1 PBX Definity

PBX is an automatic telephone exchange. A telephone exchange is a set of technical means whose task is to ensure switching of communication channels of the telephone network and automatically transmit a call signal from one telephone set to another. This is a type of communication center whose function is to connect and disconnect telephone channels during telephone conversations. The emergence and development of automatic telephone exchanges is directly related to telephony - a field of science and technology that studies the basic principles of telephone communication and develops special equipment.

1. 
   Definity Key Features

b) high productivity;

c) increased reliability achieved by duplicating the main critical components of the system;

d) increased speed and accuracy of switching for data transmission and network interaction;

e) support for computer-phone integration (CTI);

f) low monthly cost of maintenance;

g) a basic call management system that allows you to control up to 200 agents and 99 groups, providing flexible and cost-effective control;

h) notification of unauthorized access will help stop violators in the password and remote access system;

i) CallCoverage function allows you to effectively and flexibly control each phone.

3.2.2 Basic functions of the Definity system

a) abbreviated dialing - provides lists of stored numbers that can be accessed when establishing connections for local, long-distance and international calls to activate functions or to perform end-to-end signaling;

b) incoming call separation - allows the telephone operator to notify the called subscriber of a call or confidentially consult with the called subscriber so that the other subscriber on the call does not hear, and also allows the user, after answering the call forwarded to him, to call another subscriber for a private consultation;

c) automatic call - simplifies the work of the telephone operator by simplifying the switching operation to one press of a button;

d) waiting for the subscriber line to become free - ensures that calls to a busy single-line voice terminal are placed on hold and a special call-on-waiting tone is transmitted to the called subscriber. If the call is routed by a telephone operator, then he is freed up to handle other calls;

e) priority calls - this function allows you to answer calls from the telephone operator in the order of call categories. This prioritization allows calls to be processed in an organized manner during periods of congestion;

f) call hold - allows terminal users to temporarily disconnect from a call, use the voice terminal for other call purposes, and then return to the original call or connect to the original call from another voice terminal;

g) direct dialing - connects calls received over the public network directly to the dialed extension number without the participation of a telephone operator. · Different types of ringing signals - helps voice terminal users and telephone operators recognize different types of incoming calls (internal, external or intermediate);

h) emergency call - ensures the direction of emergency calls to the telephone operator. Such calls may be routed automatically by the system or may be dialed by system users. Priority processing of these calls can be performed by the telephone operator;

i) Subscriber Drop - Removes single-line voice terminal extensions from service if users do not hang up after receiving a dial tone for 30 seconds (default) followed by a pick-up tone for 30 seconds (default). These intervals can be assigned.

3.2 SMK-30 as a multiplexer

The SMK-30 network multiplexer-concentrator is designed to operate as part of a digital data transmission network (DSTN). The multiplexer works with E1/PCM-30 channels (PCR), as well as with 64 kbit/s (DC), n x 64 kbit/s channels with various subscriber terminations.

The multiplexer allows you to organize communication between remote objects via digital channels (point-to-point and group) 64 kbit/s, n x 64 kbit/s with different endings; via analog channels TC (“point-to-point” and group) with 2 and 4-wire terminations; organize channels for trunk lines (CL) between automatic telephone exchanges; channels for connecting remote analog and digital telephones to the PBX; organize a network of distributed mini-PBXs.

The multiplexer supports routing function in accordance with IEEE 802.3 Ethernet, IEEE 802.3u Fast Ethernet standards at speeds of 10 and 100 Mbit/s in full-duplex and half-duplex modes. To connect the subscriber device, standard connecting cables are used: 10BASE-T - UTP cable category 3, 4 or 5 for a speed of 10 Mbit/s; 100BASE-T – Category 5 UTP cable for 100 Mbps speed.

The multiplexer can be used in networks based on SDH and PDH technologies. The multiplexer is designed for operation in networks for various purposes, including networks of OTN and ObTS of Russian railways.

4 Individual task Cisco ME-3400E-24TS-M switch and Cisco ME-3800E-24FS-M router

4.1 Cisco ME-3400E-24TS-M Switch

The Metro Ethernet topology is organized at three levels: core, aggregation layer, and access layer. The Metro Ethernet core is built on powerful switches and ensures traffic transmission at the highest available speeds. Switches are also used at the aggregation level to connect the access layer to the core, collect and process statistics, and provide services. In some cases, when the network scale is small, the core can be combined with an aggregation layer. Most often, data transfer between the core and aggregation levels is carried out using Gigabit Ethernet and 10-Gigabit Ethernet technologies.

At the aggregation and core levels, redundancy of critical network moments is mandatory, including topological redundancy and redundancy of switch components. Using link layer technology allows for a significant reduction in recovery time after a failure. The vast majority of Metro Ethernet networks have a topology recovery time of no more than 50 ms.

The network access layer is organized according to a “ring” or “star” scheme. At this level, subscribers are connected to the network: offices, residential buildings, industrial premises. At this level, the full range of security measures, isolation and identification of subscribers, and protection of the operator’s infrastructure are implemented.


Figure 4 – Metro Ethernet ring structure
At the lower level there are Cisco ME 3400 switches, in their ring there is one Cisco ME 3800 router, which has access to a higher level, that is, the core.

The Cisco ME 3400 Series Ethernet Access Switches are 24-port devices that are designed for indoor installations serving apartment buildings, office buildings, and small communities.

Equipped with 10/100 Mbit/s ports, switches provide service to the exponentially growing traffic of end consumers, who today, as a rule, use dedicated xDSL channels. The switches are equipped with two fiber-optic ports connected to the telecom operator’s infrastructure using FTTP (fiber to the premises) or FTTN (fiber to the node) technology. Each port of the ME 3400 switch is allocated to only one subscriber; At the same time, information security is ensured at the port level. This approach eliminates the possibility of intercepting packets that are sent to users connected to different ports.

Cisco ME 3400 Ethernet switches can withstand heavy loads during high connectivity and high system resource usage. The transmission of information, video and voice is carried out at acceptable speeds for the user. Unauthorized access and traffic are excluded by connecting special security systems that can completely isolate the user from possible hacking attempts. Working with such switches is easy, fast and reliable, since transmission is carried out in a continuous flow mode.

UNI/ENI/NNI interface types:

• 
  UNI (user network interface) ports are used to connect end equipment and block traffic that is unnecessary for the user, such as BPDU, VTP, CDP and some others, and also allows you to isolate clients located in the same VLAN from interaction with each other (or allow you to select a group of ports that can communicate with each other);
• 
  NNI (network node interface) ports are used to connect two switches. They do not impose restrictions on the protocols running on them;
• 
  The ENI (enhanced network interface) port is almost like UNI, but allows you to enable individual protocols that are completely blocked in UNI.

Figure 5 – Cisco ME 3400.

4.2 Cisco ME-3800E-24FS-M Router

Cisco routers are designed to implement policies to limit access to a packet data network, combine its elements, and redirect traffic to less congested areas. The main function of routers is to quickly determine the optimal path for transmitting packets between recipients. Route selection is based on certain criteria and is based on information about the network topology and routing algorithms.

The Cisco 3800 is a high-performance series of Integrated Services Routers (ISRs). The Cisco 3800 Series routers combine security, voice, and other intelligent services into a single, compact platform, eliminating the need for multiple separate devices. Many service modules, such as voicemail modules, intrusion detection modules, traffic caching modules, etc., have their own hardware resources that eliminate the impact of services on router performance while being managed through a single management interface.

Cisco 3800 Series Integrated Services Routers include the Cisco 3825 and Cisco 3845 routers. Both routers support WAN Interface Cards (WICs), data-only Voice/WAN Interface Cards (VWICs), single high-speed WAN Interface Cards (HWICs), and an optional integration module (AIM). The differences between these routers are as follows:

Cisco 3825 routers support 2 slots for network modules. The bottom network module slot can contain either 1 single network module or 1 extended single network module. The top network module slot can contain either 1 single network module, 1 extended single network module, 1 dual network module, or 1 extended dual network module. Cisco 3825 routers also support 1 additional SFP slot, 2 built-in Gigabit Ethernet LAN ports, 2 built-in USB ports for future use, 4 single or 2 dual HWICs, 2 AIM modules, 4 PVDM modules, 24 power ports for IP phones, and hardware encryption, and VPN acceleration. Power to IP phones is supported when the appropriate chassis AC power supply is installed.

Cisco 3845 routers provide 4 network module slots, labeled 1, 2, 3, and 4. Each slot supports one of the following modules: Single Network Module, Enhanced Single Network Module, or Enhanced Enhanced Single Network Module. Slots 1 and 2 combine to support dual network modules or extended dual network modules. In the same way, slots 3 and 4 are combined to support dual network modules or extended dual network modules. Cisco 3845 routers also support 1 additional SFP slot, 2 built-in Gigabit Ethernet LAN ports, 2 built-in USB ports for future use, 4 single or 2 dual HWICs, 2 AIM modules, 4 PVDM modules, 48 ​​power ports for IP phones, and hardware encryption, and VPN acceleration.

The functionality of Cisco 3800 series routers is confirmed by the fact that the equipment supports IP telephony. Integrated support for voice functions and a fairly high density of voice ports are the distinctive features of the new line of routers. The devices provide reliable support for a large number of previously released voice modules. It is important to note that digital processors can be installed directly on the router motherboard. Today, 3800 series routers support about twenty-four digital E1/T1 ports and up to eighty-eight analog FXS ports.

The Cisco 3800 series routers are designed around switching. Such routers allow you to change performance. This means that the unique technology used allows you to combine routing flexibility and high switching performance at the same time. The transmission of data and voice streams and information processing occur simultaneously at various levels. Thanks to this processing, the throughput of switched speech and data streams increases. At the same time, the benefits of Cisco IOS routing are preserved. Provides simultaneous support for routed IP flow and switched flows.

Modern Cisco 3800 routers are centrally managed. This management allows you to reduce operating costs. At the same time, all fault reports are recorded in one place, which allows you to quickly respond to problems and quickly resolve them.

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Annotation

network communication modernization equipment

This diploma project examines the issue of modernizing the transport communication network on the Moscow - Rizhskaya - Shakhovskaya section of the Moscow Railway.

The goal of the diploma project is to modernize the transport communication network using the latest technologies for this section of the railway. To achieve this goal, the following tasks were set: analyze the existing communication network; consider several equipment options; carry out a comparative analysis of the proposed equipment and select the most suitable one with the possibility of further modernization of the network; perform calculations of the main parameters of the communication line; develop a new communication network diagram; conduct an economic calculation of the effectiveness of technology implementation; consider measures to ensure fire safety of the communication center of the M. Rizhskaya station.

Introduction

2. Technical part

2.1 Equipment selection

2.1.1 BG-20 and Artemis

2.1.4 1645 AMC Multiplexer

2.2 Development of communication scheme

3. Economic part

3.3 Calculation of tariff revenues

4. Measures to ensure fire safety of the communication center of the Rizhskaya metro station

Conclusion

References

Application

Introduction

Communication in railway transport is one of the main infrastructures. Without communication, the rapid transmission of both voice and written information would be impossible.

Previously, communications in railway transport were analogue. Analog communication does not allow the transfer of a large amount of information, and in connection with the development of the railway infrastructure, it became necessary to transmit information in large volumes, which analog communication could not provide and modernization of analog communication was impossible due to outdated equipment. Analog communication has been replaced by digital communication, which allows the transfer of information quickly and in large volumes. Over time, digital equipment was subject to modernization and the introduction of new technologies.

Currently, there is a very wide selection of digital equipment, both domestic and foreign, using various technologies and different levels of signal transmission, at different speeds.

1. Technical and operational part

1.1 Analysis of the modernization section Moscow - Rizhskaya - Shakhovskaya

This section is served by the Moscow-Smolensk branch of the Moscow Railway. The length of this section is 153.7 km. This section is divided into 15 stations, of which 3 are large (Moscow - Rizhskaya (M. Rizhskaya), Podmoskovnaya, Manikhino-1). The location of stations and the distance between them is shown in Fig. 1.1

Fig 1.1 - Location of stations in the Riga direction.

Communication equipment is installed at the LAZ node of the M. Rizhskaya station.

Primary digital communication network equipment:

1.Synchronous hierarchy level multiplexer (STM-1) SMK-30 MUX 14.2.

2. Plesnochronic hierarchy multiplexer level (E1) T-130 (2E1).

This equipment is also installed at 15 stations of the Riga direction (19 pieces of SMK-30 MUX 14.2, 2 pieces of T-130 (2E1), 4 pieces of ADM-4/1). M. Rizhskaya station has branches to UMZhD (Moscow Railway Administration), Likhabory and LAZ Moscow-Savelovskaya (M. Savelovskaya). Podmoskovnaya has branches at the Desiree depot. Manikhino-1 has branches to the Istra ticket office platform, Kubinka-1, Lukino, Manikhino-2.

Primary digital communication equipment installed on the Moscow-Rizhskaya-Shakhovskaya section is shown in Appendix 4, Fig. 1.2

The following types of communications are transmitted through SMK30:

1. Train radio communication.

2. Planning meetings.

3. Telephone devices.

4.Digital remote controls.

6. Connection with relocations.

7. Interstation communication, distillation.

8.Recorders.

9. Chipboard operators.

10. Dispatch circles.

T-130 (2E1) has 2 E1 streams, the first stream transmits voice messages and digital data to the UMZD and the second to the M. Savelovskaya station.

Access equipment:

1. Subscriber line compaction equipment.

stationary semi-set.

Switch_IP

Routers _IP

Operational-technological communication equipment:

1. SMK-30KS

3. SIEMENS OTC remote control.

Operational-technological communication equipment installed on the Moscow-Rizhskaya-Shakhovskaya section is shown in Appendix 5, Fig. 1.3

17 pieces of SMK-30 and 17 pieces of SMK-30KS are installed on the site, two large stations have branches M. Rizhskaya (UMZhD, LAZ M. Savelovskaya), Manikhino-1 through SMS-150 equipment goes to Lukino and Manikhino-2 and so from the Shakhovskaya station to the Murikovo station of the Oktyabrskaya railway.

The optical cable OKMS-A-4(2,4)SP-16(2) and OKMS-A-6(2,4)SP-24(2) is suspended on contact supports. The cable design is shown in Figure 1.4

Fig1.4 - Optical cable OKMS-A-4(2,4)SP-16(2)

OK - Optical cable;

MS - Main dielectric self-supporting;

A - winding made of aramid threads;

4 - Number of optical modules;

2 - Number of fillers;

2.4 - Nominal outer diameter of elements;

Sp - fiberglass rod;

16- Number of optical fibers in the cable;

2 - standard single-mode optical fibers.

OKMS-A-6(2.4)Sp-24(2) - self-supporting dielectric cable with an outer sheath of polyethylene, with power elements made of aramid threads, an inner sheath of polyethylene, with 6 optical modules with a nominal outer diameter of 2.4 mm, twisted around a fiberglass rod, with 24 standard single-mode optical fibers.

The distribution of optical cable fibers is provided in tables 1.1 and 1.2

Table 1.1 - distribution of cable fibers OKMS-A-4(2,4)SP-16(2)

Table 1.2 - distribution of cable fibers OKMS-A-6(2,4)Sp-24(2)

1.2 Technical characteristics of the equipment

Multiplexer SMK-30 is used to build primary communication networks

synchronous digital hierarchy (SDH) of the STM-1, STM-4 levels, organization of primary networks via cable and overhead communication lines, organization of a network of primary multiplexers n*64 Kbit/s with various endings with advanced functions and additional technological capabilities, organization of a network of routers of the 2nd and Level 3 with TCP/IP protocols and voice VoIP gateways, building a network of telephone switching stations for various purposes, organizing a network of meeting communications, organizing a network of operational and technological communication stations, video surveillance systems, security and fire alarms. Table 1.3 shows the characteristics of the SMK-30 multiplexer.

Table 1.3 - characteristics of SMK-30.

Multiplexer type T-130(2E1) is used to transmit voice messages and digital data. The technical characteristics of the multiplexer are provided in Table 1.4

Table 1.4 - technical characteristics of the T-130 multiplexer

Optical cable OKMS-A-4(2,4)SP-16(2) and OKMS-A-6(2,4)Sp-24(2) are used for suspension on contact supports of the railway network. Cable specifications in table 1.5

Table 1.5-Technical characteristics of optical cable OKMS-A-4(2,4)SP-16(2) and OKMS-A-6(2,4)Sp-24(2)

Modernization of this section is necessary since the SMK-30 equipment has only 4 external streams, and to increase the number of streams it is necessary to occupy seats. When seats (SMK-30 has 15 seats) are occupied by additional boards to increase flows, the space where you can connect the control circle, train radio communications, etc. is lost. Also, SMK-30 has 5 STM-1 ports, which is very small, and for further development of the network, a larger number of streams and STM-1 ports are needed.

2. Technical part

2.1 Equipment selection

2.1.1 BG-20 and Artemis

The BG-20 is a unique, fully integrated SDH multiplexer designed for access and enterprise networks, supporting Layer 1 and Layer 2 services. Figure 2.1

Fig 2.1- BG-20

BG-20 is a multiplexer of STM-1 - STM-4 levels, both terminal and input-output topologies. The BG-20 provides PCM, TDM, 10/100 BaseT and GbE data interfaces. Table 2.1 provides the technical characteristics of the bg-20.

The BG-20 provides the opportunity to take advantage of scalable solutions based on SDH, WDM and data technologies (Ethernet, IP, ATM, SAN), from metro access networks and client ends to the transport layer. High interface density. All interfaces are located at the front up to 6 x STM-1 or 3 x STM-4, replacing STM-1 interfaces with STM-4 does not affect the continuity of the flow.

BG-20 consists of:

1U BG-20B - basic platform

2U BG-20E - expansion platform

16VC-4 x 16VC-4 @ VC-4/3/12 cross-connect matrix

Client interfaces from STM-4/GbE to 64Kbit/s: STM-1/4, E1, E3/DS3, FE, GbEЃCFXS, FXO, 2W/4W E&M, V.35, V.24.

BG-20B Ethernet: L1/L2 with QoS and GFP/LCAS.

Working under the control of a multidimensional network management system, LightSoft BG-20 provides the ability to monitor and manage all physical and technological layers of the network.

Table 2.1 - technical characteristics of bg-20

The Artemis shelf is an all-passive optical platform that complements ECI Telecom's existing product lines such as Apollo, XDM®, BroadGate® (BG) and NPT.

Artemis integrates the most advanced filtering technology to reduce attenuation, increase signal transmission distance, and reduce overall network cost. The equipment supports interworking with any product that complies with ITU-T G.694.2 (CWDM) and ITU-T G.694.1 (DWDM), including all types of Apollo/XDM, multiplexer/demultiplexer modules, BG, and platform NPT.

The Artemis platform offers low cost, high modularity, compactness and very high density. Its passive optical module frees up slots in existing platforms for more active modules, allowing network operators to expand networks with less infrastructure investment, resulting in lower total cost of ownership (TCO).

All filters include two monitoring points, which are extremely useful for wavelength alignment.

The Artemis Shelf is available in a variety of sizes to suit the needs of every network and site. The Artemis shelf is available in the following sizes:

size 1 RU, supports 2 slots

size 2 RU, supports 4 slots

size 4 RU, supports 8 slots.

2.1.2 SDH multiplexer Transport S1

SDH multiplexer Transport S1 is modern equipment with an economical price for building STM-1 networks. Transport-S1 is designed for the Russian market and contains rich functionality. technical specifications in table 2.2

Possibility of SDH multiplexer Transport S1

* number of transmitted E1 streams: 21/ 42/ 63

* number of transmitted Ethernet 10/100BaseT interfaces: 1…18

* interface type: STM-1, speed 155, 520 Mbit/s

* wavelength of optical interface: 1310 (1550 - option)

* FOCL length: 0…120 km

* control: TCP/IP, 10/100BaseT

* service interface: 64 kbit/s

* power supply: 36/72V or 220V

The equipment can operate in synchronous and asynchronous modes and allows the use of single-mode or multimode optical fiber.

Like other modern SDH multiplexers, Transport-S1 supports remote configuration and management via TCP/IP, 10/100BaseT.

Economical price, which has no analogues on the Russian market.

Table 2.2 - technical characteristics of SDH multiplexer Transport S1

2.1.3 SDH multiplexer (STM-1) HuaweiOptiXMetro 500 (com)

The OptiXMetro 500 transmission system is designed for building multi-service corporate and city-scale operator networks; system characteristics are given in Table 2.3. The equipment can be used to organize access to transport and backbone networks, connect base stations in networks of cellular operators, connect switching stations, organize communications between LAN segments, etc. Like the entire OptiXMetro family of SDH multiplexers, the platform provides efficient transmission of TDM, ATM and IP traffic.

The transmission speed is maintained at the STM-1 level (155 Mbit/s). The equipment is small in size, characteristic of the micro-SDH device class. In networks built on OptiXMetro 500 devices, dynamic distribution of bandwidth to users is provided in accordance with the volume of passing traffic, because the system uses a statistical rather than a fixed data multiplexing method.

The system capacity is equivalent to three STM-1 threads. The cross-connect matrix has a dimension of 6x6 VC-4. In the basic configuration, the platform can support the transmission of 32 E1 streams.

Table 2.3 - System characteristicsHuaweiOptiXMetro 500

2.1.4 1645 AMC Multiplexer

The 1645 AMC is a compact device that supports 2 STM-4 and 2 STM-1 ports, as well as GigabitEthernet modules in an additional slot; Table 2.4 provides the characteristics of the 1645 AMC multiplexer.

Table 2.4 - Characteristics of the 1645 AMC multiplexer

2.1.5 Comparative analysis of equipment

The modern market for equipment for access networks, corporate networks, and railway transport networks is quite developed and offers a wide selection of equipment from both domestic and foreign manufacturers.

To select equipment, it is necessary to carry out a comparative analysis that will be used in the area described above. A comparative analysis of the equipment is presented in Table 2.5

Table 2.5 - comparative analysis of equipment

Based on a comparative analysis of the equipment, you should choose BG-20 and Artemis since this multiplexer has a low cost compared to other multiplexers, a larger number of STM-1 and STM-4 ports allows you to organize 21 E1 streams and 18 E3 streams. The passive Artemis platform reduces attenuation and provides effective support for CWDM and DWDM interfaces. Also, this equipment does not require replacement with further expansion of the network.

2.2 Development of communication scheme

To implement the new BG-20 multiplexer equipment and the Artemis passive platform, it is necessary to develop a communication circuit with the new equipment. We will place BG-20 and Artemis at 15 main stations, after which we will disconnect the OKMS-A cable from SMK-30 and SMK-30KS, then we will connect the cable to the Artemis passive platform. The next step will be to connect the SMK-30 and BG-20 multiplexer to the passive platform. After the connection has been made, it is necessary to connect the SMK-30KS and T-130 to the BG-20 multiplexer, and also connect all E1 streams that passed through the ADM4/1 multiplexer to the BG -20 which leads to the exclusion of the ADM4/1 multiplexer from the circuit due to uselessness and freeing up one pair of fibers. Tables 2.6 and 2.7 show the distribution of cable fibers after the development of the communication circuit, Fig. 2.2

Table 2.6 - distribution of cable fibers OKMS-A-4(2,4)SP-16(2)

Table 2.7 - distribution of cable fibers OKMS-A-6(2,4)Sp-24(2)

2.3 Calculation of the length of the regeneration section

It is necessary to determine the length of the regeneration section for the SDH FOSP with a two-fiber linear path based on a synchronous transport module type BG-20 from ECI, operating via an OKMS-A cable at a wavelength of 1550 nm. The required basic parameters of the BG-20 and the OKMS-A cable are given in Table 2.6

Table 2.6 - Main parameters of BG-20 and OKMS-A cable

When performing calculations, we will assume that the attenuation of one permanent optical connector, and the energy reserve

Using the data in Table 2.6, we determine the energy potential:

Substituting into formula 2.5 the value of the energy potential W = dB, losses in permanent connections, energy reserve, cable attenuation coefficient and construction length, and also taking into account that a two-fiber linear path is used, i.e. There are no additional passive components () on the cable section, we get:

If W, then. In our case, W, then using formula (2.6) we calculate the minimum length of the regeneration section, limited by attenuation:

The length of the regeneration section, limited by the dispersion of the optical fiber, is determined by formula (2.7). If we substitute the values ​​of ips/nµm into it, we get:

The smallest of the two calculated ones is selected as the maximum design length, i.e. . The obtained value is close to the value of the L-1.2 type optical interface for STM-1. To locate regeneration points, a slightly shorter length of the regeneration section is selected, which, taking into account cable reserves, can be taken as 100 km.

2.4 Calculation and plotting of transmission levels

When designing and operating a communication system, it is necessary to know the signal levels at various points in the transmission path. To characterize changes in signal level along a communication line, a level diagram is used - a graph that shows the distribution of levels along the transmission path.

To construct a level diagram, it is necessary to calculate the attenuation of all regeneration sections using the formula:

where Pout is the maximum power at the output of the optical amplifier, Pout = 17.5 dBm

The increase in OM attenuation at air temperatures below -400C does not exceed 0.05 dB;

b - kilometric attenuation in OF, b = 0.22 dB/km.

The number of construction lengths at each regeneration site is determined by the formula:

where lc is the construction length of the cable, lc = 4 km.

The total number of construction lengths for the transmission section determines the number of permanent connectors:

To calculate the transmission level diagram, we have two directions of optical signal transmission: M. Rizhskaya-Shakhovskaya; Shakhovskaya - M. Rizhskaya.

Obviously, the signal attenuation in a section for both directions will have the same value and differ in the direction of transmission of the optical signal, so we will calculate the attenuation in each section simultaneously for both directions.

For the section M.Rizhskaya - Podmoskovnaya (Podmoskovnaya - M.Rizhskaya):

For the section Podmoskovnaya - Tushino (Tushino - Podmoskovnaya):

For the section Tushino - Pavshino (Pavshino - Tushino):

For the Pavshino - Nakhabino section (Pavshino - Nakhabino):

For the section Nakhabino - Dedovsk (Nakhabino - Dedovsk):

For the section Dedovsk - Snegiri (Dedovsk - Snegiri):

For the section Snegiri - Manikhino-1 (Snegiri - Manikhino-1):

For the section Manikhino-1 - Novoierusalimskaya (Manikhino-1 - Novoierusalimskaya):

For the section Novoierusalimskaya - Kholshcheviki (Novoierusalimskaya - Kholshcheviki):

For the section Kholshcheviki - Rumyantsevo (Kholshcheviki - Rumyantsevo):

For the Rumyantsevo - Chismena section (Rumyantsevo - Chismena):

For the section Chismena - Volokolamsk (Chismena - Volokolamsk):

For the section Volokolamsk - Blagoveshchenskoye (Volokolamsk - Blagoveshchenskoye):

For the section Blagoveshchenskoye - Shakhovskaya (Blagoveshchenskoye - Shakhovskaya):

The calculation results are presented in Table 2.7.

Table 2.7 - Calculation of weakening of regeneration sections

Based on the results obtained, we conclude that the levels obtained at the reception are not lower than the minimum level of reception. Attenuation in elementary cable sections can not be compensated, which means that the installation of optical amplifiers is not required.

2.5 Calculation of reliability indicators

At the first stage, we will determine acceptable reliability indicators.

Using the formula, we determine the average time between failures. Substituting into it the values ​​=200 km, and the length of the designed fiber optic line L = 153.7 km, we obtain:

Using the formula, we determine the permissible availability factor by substituting the value and value = 1.1h into it:

We obtain the permissible downtime factor from the formula by substituting the value into it:

We will find the average failure-free operation time of linear path equipment (OLT) by substituting into it the values ​​=200 km and L=153.7 km:

Therefore, the maximum value of the permissible linear path downtime coefficient is:

To determine the reliability indicators of linear path equipment, which includes = 153.7 km of optical cable with the failure rate, the number of input/output multiplexers, with the failure rate of each, the total failure rate should be calculated using the formula:

We will find the value by substituting the value and =153.7 km into it:

Substituting the values ​​1/h and into the formula, we find the failure rate of the linear path:

Average time of non-failure operation of a linear path:

The maximum average recovery time is determined by the recovery time of the optical cable, i.e. .

Expected downtime rate:

The expected downtime rate is much higher than acceptable, i.e. >, therefore, it is necessary to take measures to improve reliability.

It is necessary to take measures to improve the reliability of the fiber optic line: replace the least reliable components of the fiber optic line with the same type of equipment from another manufacturer (with better reliability indicators), and make fiber redundancy. The most suitable measure is to reserve the linear path at the lower level to the SMK-30 multiplexer.

3. Economic part

The use of VOSP allows you to increase the capacity of communication lines. The main objective of the diploma project is to modernize the transport communication network on the M.Rizhskaya-Shakhovskaya section of the Moscow Railway. The main indicator characterizing the effectiveness of upgrading the communication network at a site is the payback period for the costs of its creation.

Payback period (Current) is the minimum time interval from the start of the project, beyond which the integral effect becomes non-negative, that is, this period, starting from which all costs associated with the innovation are covered by the total results. The shorter the payback period, the higher the value of the project.

The effectiveness of the introduction of new equipment is assessed by indicators reflecting the ratio of costs and results obtained when operating new transceiver equipment.

To determine the effectiveness of introducing new equipment, the payback period or the return period for one-time costs is also determined. In this case, the payback period is the minimum time interval beyond which the integral economic effect becomes non-negative, that is, capital costs are fully covered by the total costs of modernization.

3.1 Calculation of capital investments

Capital investments are the costs of expanding the reproduction of fixed production assets.

When carrying out modernization activities of the existing VOSP, the following capital investments are required:

For the purchase of multiplexing equipment;

For delivery of equipment;

For installation of equipment.

We will calculate capital costs according to manufacturer prices. To organize a transport communication network, we will purchase BG-20 multiplexers and the Artemis passive platform. Since the BG-20 is powered from a 220 V source installed at the stations, we will take into account the costs of a backup source. We will install the equipment in cabinets available in the cross-connection rooms of the stations.

All costs associated with the implementation of communication equipment are summarized in Table 3.1.

Table 3.1 - Capital investments for construction

Thus, the table shows that the capital costs for the implementation of the transmission system will be:

K = 1828.41 thousand. rub.

3.2 Calculation of operating costs

Operating expenses are the current (annual) expenses of an enterprise associated with ensuring its production activities.

Operating costs include the following costs:

Salaries of production personnel;

Deductions for insurance premiums;

Depreciation needs;

Material costs;

Payment for electricity for production needs;

Other production and transportation costs.

3.2.1 Payroll calculation

The amount of the wage fund (WF) for the year is calculated based on the required number of employees. The positions of the required employees and their salaries in accordance with the tariff schedule given in Table 3.2.

Table 3.2 - Payroll

Line multiplexing equipment is serviced by existing line crews. This section consists of workshops, which include one section manager, three senior electrical mechanics and twenty electrical mechanics.

In table 3.2, salaries and bonuses are given on a monthly basis. Accordingly, the wage fund for the year will be:

Full salary = 1471.14 12 = 17653.68 thousand rubles.

3.2.2 Calculation of deductions for insurance premiums

Deductions for insurance premiums reflect mandatory contributions to state social insurance, the pension fund, and employee health insurance. Deductions for insurance premiums are planned in a certain amount from labor costs included in the cost of production. Currently they account for 30.4% of labor costs, that is:

C = full salary 0.304 =17653.68 0.304 = 5366.71 thousand rubles.

3.2.3 Calculation of depreciation charges

Depreciation charges are intended for the acquisition or construction of new fixed assets. For each type of fixed assets, appropriate depreciation rates are established as a percentage of the primary cost of fixed assets.

Depreciation charges for the implemented system are set at 5% of the estimated cost and will be:

where A is the amount of depreciation charges;

K - capital investments for the implementation of the system at the project site

A = 1828.41 0.05 = 91.42 thousand rubles.

3.2.4 Calculation of materials and spare parts

Expenses for materials and spare parts include expenses for maintenance and routine repairs of communication equipment. Costs for materials and spare parts will amount to 1% of the capital investment for the implementation of the system at the designed site.

E = K 0.01= 1828.41 0.01 =18.284 thousand rubles.

3.2.5 Calculation of electricity costs

When calculating energy costs, we take into account the cost of all types of purchased energy spent on technological equipment.

We will determine costs based on the power consumed by the equipment, the number of hours and current electricity tariffs for technical needs. We will make the calculation using the formula:

El = (N q t)/ n,

where El - electricity costs;

N =3.6 - tariff for 1 kW/h, rub.;

q is the power consumption of a piece of equipment. Since BG-20 consumes 55 W, SMK-30 consumes 100 W, SMK-30KS consumes 90 W, then q=55·17+100·20+90·17 = 4465 W/month;

t=8760 hours - number of hours of equipment operation per year;

n=0.65 - efficiency factor of the power supply installation. Then the annual energy costs will be:

El = 3.6 4465 8760/0.75 = 216.628 thousand rubles.

3.2.6 Calculation of other production and transportation costs

Costs for other production, transport, administrative operating expenses are determined in the amount of 10% of the wage fund:

Epr=FZP 10%=17653.68 0.1=1765.368 thousand rubles.

We summarize the final results of calculating annual operating costs in Table 3.3

Table 3.3 - Operating costs Er

3.3 Calculation of tariff revenues

Tariff revenues are indicators of sales of communication products to various consumers at certain tariffs.

Implementation of transport communication network equipment based on BG-20 equipment of the STM-1 level to allocate up to 21 E1 streams. Therefore, the total number of allocated digital streams will be 21·17=357.

Tariff revenues of the modernized communication system consist of rental fees for E1 channels (2.048 Mbit/s) per year:

Nvols = n T 12,

where n is the number of E1 channels leased to third parties

organizations;

T - tariff for renting one E1 channel per month, T = 6100 rub.

Nvols = 357 6.1 12 = 26132.4 thousand rubles.

3.4 Calculation of project economic efficiency indicators

Let's make calculations of efficiency indicators using the results of calculations in the previous sections.

Cost 100 rub. income from core activities (cost):

C = E/Nvols 100 rub. (4.4)

C = 25112.09/26132.4 100 = 96.09 rub. for 100 rub. income.

Profit from the sale of communication services is defined as the difference between tariff revenues and annual expenses. Profit acts as the most important indicator that characterizes the final results and efficiency of business entities.

Preal = Nvols - Er = 26132.4 -25112.09 = 1020.31 thousand rubles.

The profit received by the enterprise is subject to taxation, in which a determining part of it is transferred to the federal and local budgets in accordance with current legislation.

The remaining profit after taxes is at the disposal of the enterprise and is called net profit.

At an income tax rate of 20%:

Vnal = Preal 0.2 = 1020.31 0.2 = 204.062 thousand rubles.

Net profit will be:

Pch = Preal - Vnal = 1020.31 - 204.062 = 816.248 thousand rubles.

Consequently, the net profit of the modernized communication system will be 816.248 thousand rubles per year.

The payback period of capital investments is the main assessment of the economic efficiency of the designed highway and is determined by the formula:

Current = K/Ph,

where K is the total amount of capital investments

Pch is net profit.

Current = 1828.41/816.248 = 2.24 years.

To fully characterize the designed FOTS, a system of technical and economic indicators is given in Table 3.4.

Table 3.4 - Technical and economic indicators of construction

We will calculate the net present value (NPV) and the payback period of the project using the graphic-analytical method

Net present value is the effect obtained over the service life, taking into account the discount factor.

NPV is determined by the formula:

where are the results achieved at the t-th calculation step;

Costs incurred in the same step;

One-time capital investments;

bt - discount factor.

The discount factor is determined by the formula:

where Тср - service life (1 - 10 years);

En = 0.1 - standard coefficient of comparative economic efficiency.

We will calculate the NPV in the form of Table 3.5

Table 3.5 - Calculation of net present value

Based on the data in Table 3.5, we plot the dependence of the NPV on the service life of the designed communication line.

Rice. 3.1 - Graph of net present value versus service life

As a result of calculations of the main economic indicators of laying a communication system, results were obtained indicating the economic efficiency of modernizing the transport communication network. The payback period for capital investments to create a system in the ideal version discussed above is 2.24 years, which is less than the standard period of 6 years. Consequently, the proposed project for modernizing the transport communication network on the M.Rizhskaya-Shakhovskaya section of the Moscow Railway can be considered cost-effective.

4. Measures to ensure fire safety of the communication center of the M. Rizhskaya station

Fire protection in railway transport is a set of measures and technical means aimed at preventing the impact of fire factors on people and limiting material damage to state and public property, as well as personal property of citizens from fire. In addition, fire protection includes measures to detect and eliminate the causes of fires, limit the spread of fire, ensure the evacuation of people and property from a burning room

Fire safety is ensured by reasonable organizational and technical measures aimed at preventing, detecting and extinguishing fires.

Fire protection consists of control by the relevant departments over compliance with fire prevention measures, fire prevention laid down during the design, and technical means for detecting and extinguishing fires.

Communication center workers are trained on how to properly use personal protective equipment, fire extinguishers, install fire alarms in premises, and how to act in the event of a fire.

Measures are being taken to purchase personal protective equipment and check the functionality of the fire alarm system. Fire extinguishers are refilled in a timely manner; logs are also kept on the refilling and service life of fire extinguishers, on the availability of protective equipment, on checking the functionality of the fire alarm, and on the training of communications center workers.

The floor plan of the communication center of the M. Rizhskaya station is shown in Fig. 4.1.

Fig 4.1 - plan of the communication center of the M. Rizhskaya station

In the communication center of the M. Rizhskaya station, an automatic fire extinguishing system "GAMMA-01" is installed, and a warning system for detecting fires and smoke in premises "Signal-20P" is also installed.

To calculate the evacuation time from the communication center premises, the following parameters must be taken into account. The communication center room has 3 emergency exits, the doors are 1 m wide, and 8 people work in the communication center room.

The length of the evacuation route from the farthest workplace is 15.74 meters; Fig. 4.2 shows the evacuation plan, the placement of fire extinguishers, first aid kits and the location of the GAMMA-01 automatic fire extinguishing system.

Fig. 4.2 - evacuation plan for the communication center of the M. Rizhskaya station

The volume of the room is 336.37 m3. The evacuation time t from the premises of the communication center is calculated using the formula:

where N is the number of people in the room, people;

f is the average density of the horizontal projection of a person, taken equal to 0.1 h 0.125 m;

Length of evacuation route, m;

d - width of the emergency exit, m.

D0.108 person/m,

V=100m/min, therefore q=2m/min

The fire alarm and security control panel (PPKUOP) “Gamma-01” Fig. 4.3 is designed for automatic fire extinguishing and fire alarm systems operated in temperate and cold climates. The device can be used in security and fire alarm systems, warning and evacuation management systems, access control and management systems, integrated security and life support systems for facilities. Technical characteristics in table 4.1

Figure 4.3 - Security and fire alarm and control device “Gamma-01”

Table 4.1 - Technical characteristics of "GAMMA-01"

The Gamma 01 device in our time is one of the best Russian examples of a modern fire automatic system of a new generation - an addressable analogue type system. This type of system is fundamentally different from the previous generation threshold systems due to the use of the latest information technologies in fire automatics.

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And networks"

on industrial practice

Organization of operational and technological communications based on BG-20 and BG-30

Place of internship:

Student gr. 23a

2016

Head of production

practices

Associate Professor, Department of TRSiS

Grade: _____________________

_____________________________

201__

2015/2016 academic year

Introduction………………………………………………………………………………..3

1 Main part………………………………………………………………………………….4

1.1 Construction of the primary digital network……………………………………………………...4

1.2 Equipment BG-20 and BG-30…………………………………………………….....7

2 Organization of OTS on the Khabary-Srednesibirskaya section…………………...……12

Conclusion………………………………………………………………...………………………..17 Bibliography………………………………… ………………………..18

Introduction

This work is a report on practical training at an enterprise, the purpose of which is to consolidate the knowledge acquired in the process of studying theoretical foundations.

The main direction of development of operational-technological communication networks (OTC) is the replacement of analogue switching equipment with digital equipment and its integration with digital transmission systems.

To organize operational-technological communication channels using digital transmission and switching systems, specialized switching stations are used.

Using the example of the BG-20 and BG-30 equipment, the issue of building selective telephone communication between the dispatcher and subscribers located along the railway line is considered.

Setting up a communication channel involves setting parameters for the connection ports of subscribers, which differ in location and level of administrative responsibility.

The transition to the BG platform allows you to meet the requirements of railway transport in the field of providing modern communication means, as well as increase the data transfer speed compared to SMS-150. This equipment is ultra-highly scalable by connecting expansion modules to standard BG modules and provides Ethernet over WAN/MAN networks. High traffic stability due to the redundancy of basic hardware ensures increased reliability and uninterrupted operation of all types of communications used in freight and passenger transportation.

1 Main part

1.1 Construction of the primary digital network

The development of local networks is carried out on the basis of a synchronous digital hierarchy. The main difference between SDH and PDH networks is the use of a master oscillator, in other words, a synchronization source. Removing it from the diagram will turn the SDH network into a PDH network. The main disadvantage of PDH is the inability to extract a lower-level stream from a higher-level stream without completely demultiplexing the stream, which is often uneconomical. The main feature of this hierarchy is the transparency of the multiplexing process. This makes it possible to directly allocate a 64 kbit/s main digital channel (BDC) directly from streams of any SDH hierarchy. This makes it possible to reduce the number of expensive equipment and increase system flexibility.

General features of constructing a synchronous hierarchy:

a) support as access channel signals only for tribes (trib, tributary - component signal or load, load flow) PDH and SDH;

b) tribes must be packaged in standard containers marked with a header, the sizes of which are determined by the tribe level in the PDH hierarchy;

c) the position of the virtual container can be determined using pointers that eliminate the contradiction between the fact of synchronous processing and a possible change in the position of the container within the payload field;

d) several containers of the same level can be linked together and treated as one continuous container used to accommodate a payload of non-standard load;

e) provision is made for the formation of a separate header field of size 9∙9=81 bytes.

In this section Kamen - Khabary - Central Siberian SDH hierarchy includes the STM-4 level (622,080 Mbit/s), a synchronous transport module. The collection of E1 input streams (30 channels of 64 kbit/s) through access channels into an aggregate block suitable for transport in the SDH network is called multiplexing and is performed by terminal multiplexers - TM of the access network. At this stage, containers and virtual containers are formed from E1 tribes with sequential multiplexing and the addition of routing headers with service information. Gradually, during the assembly stages, the length of the container increases, and in 8 steps the STM-4 synchronous transport module is formed.

The organization of a communication center on the Kamen-Khabary-Srednesibirskaya section is shown in Figure 1.

The SDH multiplexer has two groups of interfaces: user (tributory) and aggregate. The first group allows you to create custom structures (output of E1 or BCC streams), and the aggregate (optical) group allows you to create linear internode connections. These connections form several basic topologies.

To create fiber-optic communication networks as redundancy, a ring topology is used here, the diagram of which is shown in Figure 2.

Figure 2 – “Ring”

The main functional module of SDH networks is the multiplexer. SDH multiplexers perform both the functions of a multiplexer itself and the functions of terminal access devices, allowing low-speed PDH hierarchies to be connected directly to their input ports. It should be noted that the E1 stream in the connected device (NEAX-7400 or SSPS-128) is completely demultiplexed and the use of PDH here will not cause unnecessary costs. They are universal and flexible devices that allow you to solve almost all of the tasks listed above, i.e., in addition to the multiplexing task, perform the tasks of switching, concentration and regeneration. This section uses an optical transport platform based on dense wavelength division multiplexing technologies - DWDM (Dense Wavelength Division Multiplexing).

This is implemented using Artemis equipment. The communication network is organized on the basis of modern BroadGate (BG) equipment produced by ECI Telecom, which combines Ethernet and SDH services.

1.2 Equipment BG-20 and BG-30

DWDM technology involves spectral division of the fiber bandwidth into several optical channels. Thus, several independent channels are transmitted in parallel in one pair of fibers (each at its own wavelength), which allows increasing the throughput of the transmission system.

The BG platform offers a wide range of special features and benefits:

a) ultra-high scalability by connecting expansion modules to standard BG modules, which ensures the build-as-you-grow® principle;

b) carrier-grade ethernet over WAN/MAN networks with security, data service management and reliability of SDH technology;

c) High traffic stability due to redundancy of basic hardware and tributary protection;

d) the ability to add interfaces to a network element without disconnecting it, by installing the appropriate boards: from E1 for several ports to STM-4/STM-16/STM-64 boards;

e) optimization of network traffic at the level of one optical channel

to improve the efficiency of using existing fiber and transmitting different types of services;

e) PCM service interfaces and digital cross-switching 1/0 functions, facilitating the construction and support of various private networks;

g) multi-ADM and cross-connect functions, ideal for use in flexible network topologies such as ring, mesh and star;

h) compact and fault-tolerant, this platform is ideal for installation indoors and in outdoor distribution cabinets. Thanks to its extended operating temperature range, it is also suitable for use in harsh environmental conditions.

By providing data services, the BG platform provides the following advantages:

a) saving on capital costs (less equipment used) and optimizing the use of bandwidth;

b) reduction in operating costs due to the cost-effective integration of Ethernet and SDH into one platform with a single control system;

c) various Ethernet services implemented using one

physical port;

d) statistical multiplexing and interconnection of networks and equipment of Internet providers.

DWDM equipment st. The stone on the Ob is shown in Figure 3.

https://pandia.ru/text/80/320/images/image005_51.jpg" width="440 height=219" height="219">

Figure 4 – Application of BG

The BG-20 includes two subsystems: BG-20B and BG-20E. The BG-20B platform is a base module that can be used on its own, the BG-20E system is an expansion module that can be added to the BG-20B platform to provide more services and interfaces.

The BG-20C_DC uses 48 VDC power, has two external power line connectors, and supports dual line power for redundancy. The appearance of the front panel is shown in Figure 5.

Figure 5 – Front panel of the BG-20C platform with DC power

The BG-20B platform has one connector used for power module configuration. The MXC-20 board combines a cross-connect matrix, a synchronization unit, 2 STM-1/4 interfaces and 21 E1 interfaces. The appearance of the front panel is shown in Figure 6.

Figure 6 – Front panel of the BG-20B platform

The BG-20E shelf is an extension or slave device of the BG-20 platform and must always be connected to the BG-20B shelf. The appearance of the front panel is shown in Figure 7.

Figure 7 – Front panel of the BG-20E platform

The BG-30 supports interoperability with the XDM and BG-20 platforms in all aspects, including SDH, PDH, data links, DCC, management and other network layer functions. The appearance of the front panel is shown in Figure 8.

Figure 8 – Front panel of BG-30B

The shelf consists of the following parts:

a) two connectors for power supplies;

b) one slot for the main control processor MCP30;

c) two connectors for XIO30 boards;

e) three slots for traffic cards (Tslots).

The BG-30E contains three expansion card slots supporting various types of PDH, SDH, Data Link or PCM expansion card networks. The appearance of the front panel is shown in Figure 9.

DIV_ADBLOCK82">

Figure 10 – Redundancy using dual fiber

2 Organization of operational and technological communications on the Kamen – Khabary – Srednesibirskaya section

The creation of a digital OTN network should be carried out simultaneously with the digitalization of the primary OTN network. The OTN network must be built on a primary digital stream of 2.048 Mbit/s, which is formed on individual fibers of the fiber-optic line using hardware included in the switch, or separated from the digital primary network.

Half of the channels of one stream of 2.048 Mbit/s are intended for organizing group OTS channels, the rest of the 64 kbit/s BDC of this stream and three other primary digital channels (PDC) can be used to pull dispatch circles to the control center, organize a grassroots data transmission network (PD) ). The structure of the BCC channels of the first digital stream of 2.048 Mbit/s should provide a group channel mode for organizing all types of dispatch communications.

Peripheral equipment remains analog at the initial stage. A cable with copper conductors is used to reserve the main types of OTS and organize cross-country communications (OGC), interexchange communications (IOC).

A certain disadvantage of the described OTN system is the organization of group channels assigned to each type of dispatch communication, and the low utilization of the capacity of the fiber-optic communication line creates the prerequisites for building an integrated network for all types of communication.

The hierarchical construction of the OTS system provides for the presence of a three-level communications structure, and involves the inclusion of part of already existing and newly constructed information transmission systems. The existing scheme for constructing an OTS system based on BG-20 and BG-30 is shown in Figure 11.

Figure 11 – Scheme of constructing an OTS system based on BG-20 and BG-30

Level 1. It is proposed to use the SDH network under construction as backbone switching channels. In the support centers, SDH BG-20 and BG-30 switches are installed, interconnected by backbone fiber-optic communication lines. These switches provide access to a high-speed network at 2048 kbit/s streams to the following levels of the system, which are shown in Figure 12.

Figure 12 – Connection diagram of OTS system levels

Level 2. The main task of this level is to ensure the creation of a group channel and the connection to it of a number of subscribers of various types. This ensures compatibility of the interfaces with existing analog equipment. At this level, SSPS-128 converters connected by ISDN PRI channels and NEAX 7400 ICS M100MX stations connected by OKS No. 7 channels are used. In this case, SSPS-128 and NEC M100MX are connected at one station. The block diagram is shown in Figure 13.

Figure 13 – Connection diagram of the logical structure of the OTN network

Level 3. This is the level of switching equipment where NEAX 7400 digital stations are used. Its task is to ensure the functioning of consoles and other OTN subscribers, as well as their interaction with level 2. For this, a separate E1 stream is used, which connects NEAX 7400 and SSPS-128. In the event of a physical break, a backup line is provided through one of the racks of neighboring stations. This capability is determined by the hardware of the switching station. (This has been implemented on the Khabary-Srednesibirskaya section.)

The individual rings are connected to each other as shown in Figure 12, using a bridge converter.

The bridge converter performs the following functions:

a) supports the upper-level transit flow;

b) connects the group channel with the lower-level controller through one E1 stream, while 30 group channels can be switched from the upper level to the lower one.

Application options for the SSPS-128 converter:

a) group channel controller;

b) a control device that interacts with a digital transmission system;

c) switching and channel-forming equipment with a dedicated MCC, OCC, data transmission channels;

e) provides access to the group channel for switching station subscribers;

f) includes equipment for connections;

g) four wired PM channels;

h) two-wire terminations for organizing analog branches from the digital network via physical lines;

i) two-wire terminations for organizing communication via physical communication lines;

j) two-wire terminations for connecting MZhS lines;

k) radio stations;

l) negotiation registrars.

The converter is a metal case shown in Figure 14.

Figure 14 – SSPS-128 converter

The switching station shown in Figure 15 is supplied as a case with an installed PZ-PW121 power supply and BWB motherboard. The case has sockets (slots) for installing electronic boards. The system board contains connectors for connecting electronic boards, LTC0-3 connectors for connecting installation cables (output to the cross-connect) and connectors for connecting power supply cables. The set of these boards determines the functionality of the station. For example, Art. Plotinnaya allows you to connect OTS and city subscribers to one NEAX-7400 station by installing an additional flow board, with which it is connected to the Definity PBX hub station at the station. Stone-on-Obi. Thus, 4 E1 streams are connected to the NEAX-7400 station.

Figure 15 – Switching station NEAX-7400

The group channel of digital technological communication is organized using digital transmission and switching systems.

A synchronous STM-4 level multiplexer operating via a fiber-optic communication line is used as a transmission system.

Switching stations for administrative and executive purposes implement the technology for connecting subscribers to a group channel. The group channel adopts the dispatch control principle, which consists of the presence of a dispatch center and subordinate intermediate points of subscribers. The dispatcher has priority in the process of negotiations with subscribers, which consists in the possibility of interruption of the speaker. Intermediate points are called using the selective calling method.

The presence of transmission and switching functions in the group channel served as the basis for the ring technology of its construction. There are rings of the upper and lower levels.

Basic principles of group channel operation:

a) guarantee that the subscriber will receive messages from the dispatcher;

b) minimizing the passage of noise, interference and echo into the group channel;

c) compatibility with all types of analog equipment (including PU4D and US 2/4);

d) widespread use of digital devices;

e) the possibility of using conventional analog telephones;

f) the possibility of full-duplex operation for digital devices and remote controls (in some cases, analog devices);

g) switching of overhaul communication lines (OCL) directly into the group channel;

h) the possibility of using reception and transmission amplifiers;

i) widespread use of voice control devices (VCD).

Conclusion

At the Kamensky RCS enterprise, during the internship, the necessary skills and practical work experience were mastered and acquired.

The practice began with familiarization with internal labor regulations, conducting introductory briefings, and studying instructions on fire safety and labor protection. Next, acquaintance with the equipment of the RCS enterprise - 4 st. was carried out. Stone - on - Ob. The work was also carried out under the supervision of a supervisor.

To compile the report, information obtained during the internship was used, as well as information obtained from technical documentation and information taken from electronic resources.

The first section discussed the principles of constructing a primary digital network and the structure and general information about the BG - 20 and BG - 30 equipment.

The second section analyzes the organization of operational and technological communications on the Kamen – Khabary – Srednesibirskaya section.

Bibliography

1. Communication center passport Art. Stone-on-Obi

2. Official website of the Telecom Networks company. Electronic resource http://www. telecomnetworks. ru/vendors/eci/broadgate/bg20/

3. DWDM systems: features and applications. Electronic resource http://www. ccc. ru/magazine/depot/03_04/read. html?0302.htm.

4. Gorelov, G.V. Telecommunication technologies in railway transport. Textbook for universities Department of transport / G.V. Gorelov, V.A. Kudryashov, V.V. Shmytinsky and others. M.: UMK Ministry of Railways of Russia, 1999. 576 p.

5. BroadGate® family of products. General description.