Testing hardware print servers. Which print server to choose

After you have configured thin clients, the question arises of how to configure printing from these thin clients, and even many users are blocked USB ports so that they don’t poke anything other than the mouse and keyboard? This is exactly why a print server exists. We placed the printer in the middle of the office and connected it to corporate network, shared and enjoy the round dances of users around it)))

I spent a long time choosing among many models of this equipment and still settled on TP-LINK TL-PS310U v2

This device attracted my attention because it advertised a bunch of printers via a USB port and the price was quite reasonable ( full list see the manufacturer's website for supported devices). After I received this print server I started testing it in combat. First I installed the driver, or rather the utility that came with the disk, but I didn’t download it from the Internet because they were the same version as on the disk. Installation is not difficult even for a “housewife”.

Setting up a TP-Link print server

Then I connected it to the local network. Default IP is indicated on the bottom cover of the device, but for me it perfectly received the IP via DHCP the first time and was determined in the utility

As you can see in the screenshot, we can copy parameters, firmware from this menu, and also update the firmware and set a password to access this print server.

Now let's try to connect the printer to it, I started from the hardcore by hooking it up to an HP LaserJet 1100 that connects via an LTP port, I hooked it up via an adapter from LTP to USB. The print server found that there was equipment connected to it and showed that it was a USB printer. We activate the printer as a device in the utility and it starts standard installation network printer

Note. Immediately after the printer is detected and the drivers are installed, uncheck the “turn off the printer when idle for 30 seconds” otherwise you will get the printer constantly falling off after 30 seconds.

The printer installed without any problems, it works and does not cause headaches.

Then I decided to go even further and check how it works this device with modern MFPs, I hooked it up to an HP LaserJet M1132 and that’s where the problems started... Because. our print server can still work with storage devices; first of all, it determined that a remote network drive, it turned out that the printer was first identified as a network drive with drivers written to it. Decided this problem by installing drivers from the official HP website for this MFP. Then I connected the printer again, it was identified again as a storage device, unchecked the " automatic shutdown"storage device" and after 40 seconds a miracle happened, the network drive was disconnected and automatically identified as an MFP. The drivers were delivered automatically. Again, do not forget to uncheck the "turn off the printer..." box. After all these manipulations, the MFP worked correctly, just like a printer and the scanner. After rebooting or turning off the computer/printer/print server, the print server shows that the storage is connected again, but after ten seconds it detects the MFP and starts working as it should.

In the end, I would like to summarize that, in principle, the device is good, it works without freezing and supports a bunch of devices (judging by the information on the network, even printers that are not advertised, I didn’t have a chance to check it myself because there is no such exclusive one). I managed to test it myself on a couple more Canon and Xerox devices, and the flight was also normal. I can say unequivocally that I do not regret purchasing these print servers, there are practically no problems with them and there is practically no brand (I don’t think initial setup) compared to the same original ones from HP, universal ones from D-Link.

In companies that have a small to medium sized local network, a fairly common option for network printing is to use a small local printer, which is connected to one of the computers on the network. The main advantage of using this option is cost-effectiveness. However, when implementing this option, printing uses additional resources of the computer to which the device is connected, which leads to a significant decrease in its performance. Dedicating a separate computer just for network printing is financially expensive, especially if the required print volume does not exceed the capabilities of the printing device. The solution to this problem may be the use of the so-called print server.

The print server (print server) is small device, connected to the local network (cost from $40), to which they connect one or more printers(the number of connected devices is determined by the type of device). Exists two types of print servers: internal and external. External print servers in most cases they work with any devices, regardless of the manufacturer, and internal exclusively with printers from the print server manufacturer. But regardless of the type of print server, it is “transparent” to operating systems and requires only the correct configuration of parameters for the data transfer protocols used on the network.

Basically, print server models differ in the type and number of ports used to connect printing devices, network speed, dimensions, as well as the range of network protocols that it is capable of supporting and, as a result, the ability to work in a “multi-operational” network (that is, a local network, to which PCs are connected operating systems various types).

The print server comes complete with proprietary software that allows you to administer the work and has advanced or not advanced diagnostic and configuration tools. Basically, this software allows you to work only with devices from the print server manufacturer.

Depending on the manufacturer and model of the print server There are several options for "behavior" it on the local network. When some models are connected, they are displayed in the network environment as a separate computer with printers connected to it. IN in this case To install the printer on a work computer, the usual algorithm used to connect a regular network printer is used. In this case, there is no need to install additional software from the print server developer to the client machine. Administration of the print server is carried out only from the computer on which the configuration software was installed. In another case, to install a printer that was connected to a print server, the client part of the software must be installed and configured on the user’s computer. In this case, the client program emulates the local port of the printing device on the computer.

Connecting the print server

• Blog of the company "NBZ Computers"

• Tutorial

Today we will test D-Link print servers connected to an OKI printer.

Of course, the optimal solution in this case would be to use the original OKI print server, which is network card, built into the printer and working directly with the system bus. This solution allows you to obtain a completely transparent connection between the computer and the printer via the network, since it provides control of the printer through the web interface of the network card without restrictions on functionality, and the network parameters are configured through the printer control panel. In addition, when using a network connection, it is possible to use such software products, like PrintSuperVision and, even more interesting, PrintControl.
And everything would have been fine if not for the crisis. It is well known that the original network cards that printers are additionally equipped with are quite expensive devices. So I’m thinking about a more affordable, and also a little more flexible option - an external print server from another manufacturer.

And so we decided to test several inexpensive and very popular D-Link print servers with OKI B400 series printers.
OKI selected the B410d printer as a test subject. This model is equipped with an IEEE-1284 parallel port and a HiSpeed ​​USB2.0 port. We connected the compact print server DP-G310 to the printer via a USB cable, which combines the functions of wired and wireless communication. Tiny box, barely sized more smartphone, is equipped with 3 connectors: Ethernet (operating speed up to 100 Mbit/s), USB2.0 and a power connector. In addition, a screw-on wireless antenna is nestled between the network and USB connectors.

First test - working via a wired network with OKI
By connecting the box to wired network Ethernet, we ran the management utility, which found the print server on the network and allowed us to configure its IP address.

It was most convenient to do further configuration through the print server’s web interface, which is what we did.

Here, as you can see, the basic settings of the network connection are shown (the address was obtained from the DHCP automatic addressing server) and you can see the status of the printer connected via USB port(in this case it is in ready mode).
Next, we configure the wireless communication parameters: specify the type (infrastructure) and launch the review.

And voila - we can print on a printer via a radio channel! Another tab gives quite significant information about the nature of the printer that is supported by this print server:

Only printers that can print directly from DOS can be connected here, that is, if we are talking about laser printers, then these must be printers that support PCL5/PCL6 system commands. As is known from the performance characteristics of the B400 series printers, these devices are just that. In addition, other cost-effective printers also support such functions, for example:
B411d
B431d

Test 2 with multi-printer server

Now let's try something more powerful. We were offered the DPR-1061 model for testing - a universal print server through which you can connect even 3 printers at the same time!

Print server D-Link DPR-1061, capable of serving up to 3 printers simultaneously

D-Link DPR-1061 print server: one parallel port and 2 USB2.0 ports are used to connect printers

By connecting the device to the local network and accessing it using the default IP address specified in the instructions with a browser, we can see the internal website. The first thing you need to do is install network printers. And here the installation process is solved quite interestingly:

The Network Printer Setup Wizard prompts you to run small program: it is stored directly in the memory of the print server and, after loading from there, can be immediately launched (do not forget about the necessary rights to install the printer and that you need to allow the launch of the program downloaded from the website). With its help it is very easy to detect printers connected to the device and install their drivers:

After installing the printer driver, in its properties in the Ports tab, you can see that work is done through a standard TCP/IP port, which is called usb1, usb2 or lpt, depending on which port the printer is connected to.

However, the names for the ports can be changed in the same place in the Setup section of the internal website:

From the Maintenance section of the internal website, after installing the printer, you can verify its functionality by printing a demo page (using a standard Windows test page):

That's it, you can print! Again, no miracle happened with the GDI printer, but the B400 series PCL printers worked successfully both via USB and via a parallel port.

Test results
In general, this is a fairly positive, although quite expected, result: honest print servers work transparently and reliably with honest printers. So those who are looking for a reliably working solution for connecting a printer to a network can be strongly advised to pay attention to OKI printers in combination with D-Link print servers.

Sergey Lebedev training manager and technical support OKI dealers

Manufacturers offer various models external print servers that allow you to connect regular printers to a local network. These print servers can be either a simple “box”, in which on one side there is an RJ-45 connector for connecting network cable, and on the other a parallel port connector, or a connector for connecting a USB cable. Or it could be a more modern, combined solution, which is, for example, a wireless network access point, a network hub, a VPN client and a print server connected to the printer via a USB port. But regardless of the physical implementation of the print server, the method for installing network printers will be similar.

First of all, you need to install the print server itself. This is done in accordance with the instructions attached to it and using the software supplied by the print server. Usually this special program, which at a minimum should perform one important function for us: set the print server to an IP address and subnet mask corresponding to the addressing accepted on your local network (for example, address 192.168.2.112 and mask 255.255.255.0). After we have set the IP address, we need to check its functionality. To do this, at least ping it, but it’s best to go to its internal website by entering the IP address set in our print server in address bar browser. Having made sure that the print server is visible on the network, let's proceed to installing our printer.

To install a network printer on a local network via an external print server, you need to go to the “Control Panel” then “Printers and Faxes”, in this window select “Add a Printer”, the “Add Printer Wizard” will start. Please note that despite the fact that in this case the printer will be a network printer, we select the “Local printer connected to this computer” option, then activate the “Create a new port” option and select “Standard TCP/IP Port” from the list (in some cases, an alternative option from the print server manufacturer:

This is the most universal and simplest option for setting up a network printer on a local network through an external print server, which works in most cases. However, print server manufacturers may offer alternative options implementations of the IP stack for printing and these options can be automatically installed during the installation of the print server using the program included with it. By clicking on the "Next" button, we will be asked to enter the IP address and queue name for our network printer. Here you need to enter exactly the address that we assigned to our print server at the stage of its installation. The queue name is usually any word you like. However, in some cases it is necessary to use the queue names specified in advance by the print server manufacturer, without which the printer will not be able to work! Most likely, after this another window will appear informing you that the type of network device is not recognized:

In this case, you can leave the Generic Network Card option, or look in the list for the option in the best possible way corresponding to your print server. The most the best option in this case, the name of your print server will be in the list (usually appears if the print server is installed from the disk supplied with it). Now network printer configured via an external print server on the local network. Also, a network printer on a local network can be configured for general use by connecting to one of the computers on the network or through the built-in network card of the printer itself, if available.

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Andrey Borzenko

Today, printers directly connected to the network have become traditional office equipment. They provide fast printing And easy installation regardless of location, which is so important for network administrators. However, in organizations with local network small and medium scale, the most common option for collaborative network printing remains personal printer, connected to one of the PCs (Fig. 1). The main advantage of this option is cost-effectiveness. However, it should be remembered that this printing method uses the resources of the PC to which the printer is connected, and the computer's performance is significantly reduced. So, with large volumes of network printing, it becomes very difficult to use this PC for its intended purpose. Dedicating one computer only for network printing, as well as purchasing a special network printer, is often unjustified from a financial point of view, especially if the printing volumes do not exceed the capabilities of the printing device used. So-called print servers, or print servers, are designed to help solve this problem.

Print servers are small network devices, to which one or more printers can be connected (Fig. 2). They come in two types: external and internal (Fig. 3). The latter are made in the form of a board and, as a rule, can only be used with certain printing devices. The most notable limitation of internal network cards is that a specific printer must support them. This means that if the printer was made before the advent of such devices or if the printer is new, but internal maps it does not support, you will have to apply external device network printing.

Rice. 2. Print server for two printers.

Rice. 3. External and embedded print servers.

Additionally, the internal board only serves one printer. External print servers can support multiple printers simultaneously, thereby saving on additional ports. Having a single device handle many printers also reduces configuration needs and resources. For example, one IP address is enough for each printer, while printers with an internal board will have to be allocated a separate address for each one.

Often internal network cards have restrictions on the number of supported network protocols and their simultaneous support: it happens that required protocol is not supported or the two protocols cannot operate simultaneously.

An external print server enables transparent, network printer sharing. Same as network computer with a printer connected to it, the external print server has its own network connection, and the printer (or printers) connects directly to the server. In this case, there is no need to spend money on purchasing and maintaining a relatively expensive PC - instead, an inexpensive, small-sized, easy-to-use device is used.

Advantages of external print servers

Print servers are usually recommended to be installed in medium and large networks, where required remote control printing devices. Their use is especially effective in cases where there are many printers on the network located on different floors and even in different buildings, and it is necessary to provide the administrator with maximum management capabilities, and the user with maximum convenience for working with them.

Saving money

To print from a computer or file server with a connected printer, you need to have this computer or server, and they are quite expensive. Costs increase significantly if multiple printers needing network access are distributed throughout the office. Even the simplest computer is significantly more expensive than a powerful multi-protocol print server that can support multiple printers simultaneously. In addition, the print server allows you to reduce the time spent on support and service (computer maintenance requires significantly more time).

Main processor offload

Processing print jobs takes up a lot of CPU time on the computer to which the printer is connected. If at the same time the PC performs other tasks or provides files to general access, the seal can significantly affect his ability to perform other tasks. Printing performance also leaves much to be desired if the computer simultaneously performs several tasks that significantly load the processor.

The reason for the high load on the processor is the so-called software character-by-character I/O mechanism. Its essence is that when the server sends a print job to the printer, a processor interrupt is initiated for each character. It does not matter which computer is used - an outdated XT or the fastest Pentium 4-based machine. The requirements for the server increase significantly if it serves several printers.

The print server uses DMA (Direct Memory Access) instead of software character-based I/O. In this case, the processor interrupt is triggered only for entire data packets. This way, the print server not only frees up your computer or file server so it can perform other tasks more efficiently, but also allows you to achieve faster network printing.

Convenient accommodation

When connecting printers to a computer or file server there is no need to choose their location. And since servers, for example, are usually located in a secure, specially air-conditioned room or closer to the system administrator, they are often inaccessible to most users who have to make long “walks” to pick up documents sent for printing. Network print servers, on the other hand, allow you to place printers anywhere on the network, exactly where they are needed most. Due to their small size, such devices can be connected directly to the printer or placed in places where they do not interfere with anyone.

Additional job processing

Often in a heterogeneous network environment, print jobs created on different operating systems or networks require additional processing before being sent to a particular printer. For example, many print jobs created on UNIX require "carriage returns" to be inserted at the end of lines, otherwise the printer will print the text in a "ladder" manner. Another standard pre-processing requirement is printing title page for each job so that users can find their documents in the printer output stack. In many cases, the printer needs to be configured differently for different users.

This feature is often provided on print servers using virtual printer technology, allowing significant savings on the purchase of additional printing devices. In this technology special virtual printers configured directly on the print server. Users submit their jobs to the virtual printer and the jobs are pre-processed according to predefined conditions. For example, one virtual printer can be used to insert carriage returns in jobs from UNIX computers, another can be used to convert ASCII jobs to PostScript for users whose applications do not support this format, and a third can be used to prioritize jobs from users who require provide a certain level of security. In addition, all virtual printers can be configured to print a cover page. The advantage of a print server is that all these virtual printers are located on one server and all users are served by one physical printer.

Control options

It is vital for network administrators to know what is happening on the network. When the server is entrusted with printing, it generates messages about the status of print jobs, the number of pages printed, and notifications about printer problems such as printer inaccessibility, paper jams, or missing paper. These messages are sent directly to the network administrator via email or are logged in the system log.

In addition, print servers often support software management SNMP protocol, giving you full control over standard SNMP applications such as Hewlett-Packard's OpenView, Sun's SunNet Manager or SNMPc Castle company Rock.

Print server capabilities

Print servers are currently produced by companies such as Axis Communications (http://www.axis.com), Digi International (http://www.digi.com), D-Link Systems (http://www.dlink .com), Hewlett-Packard (http://www.hp.com), Intel (http://www.intel.com), Lantronix (http://www.lantronix.com), Lexmark (http:/ /www.lexmark.com), Microplex Systems (http://www.microplex.com), NetGear (http://www.netgear.com) and others (Fig. 4). These devices are slightly larger in size than a regular video cassette. Each of them has a connector for connecting a power supply, an RJ-45 Ethernet 10/100 Mbit/s socket and several printer ports (parallel and serial). Some devices have built-in hubs. Typically, all print servers can simultaneously handle text printers and PostScript printers. Most printers on the market are compatible with these servers, but there are some that do not work with them. These are inexpensive printers, such as the HP DeskJet 700, 820, or 1000. They use Windows 95/98 to perform most of their image rasterization functions and only function when connected directly to a PC running one of these operating systems.

Rice. 4. D-Link DP313 print server.

With built-in Web servers, all print servers can be configured using a browser. New devices usually support IPP (Internet Printing Protocol). Automatic IP address assignment and intuitive printer naming with DHCP and WINS/DNS support make installation and configuration easy. Each device can perform a test print or display a status printout containing information about its IP address, active protocols, the number of documents in the print queue, the types of printers connected to it, and other information. Some print servers are equipped with a special test button, when pressed, a diagnostic printout with information is displayed on the printer. In most cases, the print server is able to determine the type of connected printer and the necessary network protocols. Automatically sensing data speed and media eliminates the need to configure these settings during installation.

Typically, each print server comes with a CD-ROM with configuration and management utilities. Because new print servers have an open architecture, they can be updated by downloading new firmware stored in flash memory. This allows print servers to adapt (at least for some time) to ongoing technical changes.

To network servers and client PCs could work with the print server, they must be configured correctly by installing drivers for new network printers on them. There are two main configuration methods: the first involves creating a virtual local printer port (on a PC or server) using software supplied by the print server manufacturer, and the second is using the new IPP protocol (if the client OS supports it). Some print servers have special means, with the help of which an installation disk is created for a new network printer, containing the driver for this printer, as well as information about the IP address of the print server and the password for accessing this printer. You can install the printer driver in another way - using the IPP protocol.

Speed ​​up printing

The printer is the bottleneck in almost any printing configuration. Print servers are capable of delivering speeds much faster than a standard computer parallel port, and in most cases deliver data faster than it can be processed. regular printer. For example, Microplex print servers are equipped parallel ports with a performance of more than 200 thousand characters per second. A standard computer parallel port transmits approximately 30 thousand characters per second.

Here it should be emphasized once again that print servers support most well-known printing devices - from the latest laser to the oldest dot-matrix printers. In addition, any printing languages ​​are supported, such as PostScript, PCL, HP-GL and others. The print server doesn't care what type of data passes through it. It simply forwards the data transparently to the connected printer or printers. The only exception is when special data processing is required, such as conversion from ASCII to PostScript. In this case, the print server looks only at the beginning of the data to determine whether conversion is required.

Generally speaking, to evaluate printing performance, it is necessary to know the bottlenecks of this process. So, when preparing a job for printing word processor takes the time to convert a document from its native format to a printer format such as PCL or PostScript. The conversion process depends on the size of the document and the performance of the word processor when performing this operation; it can be quick or take a fair amount of time. Conversion time also greatly depends on PC performance. The time it takes to transfer a job from the word processor to the print queue is called swap time. It is determined by factors such as performance application program as data moves to the printer port (or print queue), and network performance when transferring print data and queuing it. The time a print job waits to be printed is called wait time. It depends on a number of factors, including the number of jobs in front of it, their size, the speed of the server and how it is used. The print server periodically checks the print queue, if there is one at all, to see if there are jobs to print. If there is such a queue, and the printer is online and ready to accept, then the print server will begin to move the job from the queue to the printer. This process is called unpaging or dequeuing, and the time it takes to move the entire print job to the printer is called unpaging time. Factors that control unpaging time are the speed at which the print server can remove data from the print queue and the speed at which it routes that data to the printer. Another key factor is the speed at which the printer receives data.

As practice shows, it is the time when pumping is removed that often has the maximum impact on network system print. In a well-organized network printing system, latency is usually low because the print job is often the only one in the queue. In this case, once the word processor has finished paging, the only thing left for it to do is print, which will take unpaging time depending on the print server.

Print servers serve all jobs on an equal basis using the FIFO principle: First In - First Out, i.e. there are no preferences for individual computers or networks. Each I/O port typically has its own queue, which is processed independently from the queues of other ports. Thus, a print server with four I/O ports (two parallel and two serial) can support four queues, each serving its own printer. The ports support printing simultaneously without the risk of jobs getting mixed up or lost.

At any given time, the print server stores only a few kilobytes of data per I/O port, with the remaining data stored at the job source. There are simply no print servers on the market today that can fully spool print jobs, so the source computer is always involved in job spooling. In most cases, this operation is performed very quickly.

Access control

If the print server is not equipped with security features, then no matter how many security mechanisms are hidden in the network OS, the network administrator receives open system, where there is no way to prevent access by users who do not have sufficient rights. The ability to restrict access to a printer has significant potential benefits. In particular, unauthorized use of a printing device leads to increased costs for maintenance and consumables. If the printer prints unauthorized jobs, then it is not available for urgent business projects that have tight deadlines. The consequences of poor printer usage controls can be more severe if print servers support printers that print checks, accounts payable, and other accounting documents. In many cases, access control can prevent serious negative consequences that could result from unauthorized printing in institutions that handle confidential documents.

In many cases, network administrators organize a centralized queue of print jobs. Users submit jobs to a centralized queue on the file server, which then forwards the jobs to the print server, which in turn forwards the job to the printer. Thanks to this discipline system administrators can centrally manage all user print jobs. This allows you to use network operating system capabilities such as automatic download printer driver when connecting to a queue, while maintaining the performance and location freedom of print servers.

In some situations, sending print jobs to a centralized queue is either impossible or ineffective. An example would be a remote office equipped only with workstations and connected to the headquarters by a slow communication channel. It is often impossible to create a centralized print queue, either because the file servers are overloaded or for other reasons. In situations like this, it makes sense to have workstations print directly to print servers. Print servers support both sharing, and direct printing.

Since network OS security features can restrict access only to the file server's print queue, you can use any computer connected to the network to send a print job directly to the print server, bypassing network OS control. A reasonable solution in this case is to equip the print server itself with security measures.

One solution to the problem of unauthorized access is the use of technology password protection Intel. This technology complements the security features found in most network operating systems. A security check is performed whenever a user attempts to print directly to a network printer, bypassing the security features of the network OS. For example, with Intel NetportExpress 10 and 10/100 print servers, administrators can set a password for any connected printer. In an environment with sharing printing, for example when users send print jobs to a queue on Windows server NT, the administrator can configure the NT server settings so that it forwards jobs to the print server with a password. The file server is the only computer that needs to know this password. The administrator controls access to the print queue using normal network OS security features. It should also be noted that in a situation where workstations print directly to a printer, there is no centralized queue of print jobs on the network and the network OS does not control access to the print server. Anyone can use the printer. This technology overcomes this limitation by replacing the security features of a network OS. Only those users who know the corresponding password can print documents to a specific printer from their workstations. If workstation If the password is incorrect, the print job simply fails, as if the printer were not connected to the network at all. So, if an administrator has three printers connected to the same print server, then any of them (or all of them at once) can be equipped with a unique password. For example, if monochrome laser and color inkjet printers are connected to the print server, then access to laser printer can be allowed to everyone, and access to color inkjet printer Restrict with a password. Printer passwords can be used to UNIX systems, Linux, Windows NT, Novell and even AS/400.

Today, for most new devices you can limit network access to them and to their individual printer ports. Such a restriction may be required, for example, if the printers contain special paper (various types of forms, forms, etc.) or if you need to ensure printing only through a file server (working under Linux control, NetWare or Windows NT). If the print server is configured to allow access only to the file server, then users will not be able to bypass the file server by interacting directly with the print server. Print servers also have the ability to restrict access to their Web interfaces using a password.

Protocol support

In heterogeneous network environments, administrators must support many different print services and protocols. Print servers enable multiple network users to print to the same printer using different network protocols. So this is great way reduce the cost of a workplace. Users can use the same printer even if they are working on different platforms. Modern servers Printers usually support TCP/IP, IPX, DLC/LCC, AppleTalk/EtherTalk, NetBIOS/NetBEUI, LAT protocols, making them possible to use even in mixed environments. As for printing protocols, they usually include LPD, RSHD, FTPD, direct connection, PSERVER, RPRINTER, LPD, print manager, etc.

With constant growth computer networks The process of managing printing in them also becomes noticeably more complicated. Print servers are designed to solve this problem. And the more “smart” they are, the more features will begin to take over, the easier it will become for the administrator to decide network tasks, and users will be able to work much more efficiently. Online printing has undergone fundamental changes in recent years, and there is no end in sight to this process of change in the foreseeable future. Companies want enterprise-scale remote printing solutions, and network administrators interested in tools that would simplify management and provide greater centralization of printing processes.