Types of SIM cards for phones, sizes. Differences between SIM card formats and how to change their sizes

Mini— sim- this is an ordinary and familiar SIM card, standard size, which is usually called a “sim card”, without the “mini” prefix. The most common format of SIM cards, but today they are increasingly difficult to find in new smartphones.
Regular size standard SIM card or mini-sim – 25 X 15mm

Micro— sim- this is the same SIM card as a mini-SIM, but unlike it, a micro-SIM has a smaller size of 15 X 12mm. As a rule, SIM cards are sold with the ability to turn a regular SIM card into a micro-SIM card by simply squeezing a micro-SIM out of the plastic frame of the card.

A universal or multi-SIM card looks like this (you can see the boundaries along which you need to squeeze out the required SIM card size):

What is a Nano SIM card?

Nano— sim- This is the newest SIM card format, and today it is the smallest SIM card size for smartphones and tablets. The Nano SIM does not have any plastic around the chip like you see on the Mini SIM and Micro SIM. The size of a nano SIM card is half the size of a standard SIM card and is 12.3 X 8.8 millimeters, which is practically the size of the chip itself, but still has a small border.

Micro-SIM and nano-SIM: the difference is in the size of the plastic or in the chip?

Based on the above characteristics of SIM cards, you can notice a significant reduction in plastic, directly along the edges of the SIM card chip. The sizes of SIM cards are the key and main feature of what the SIM card is called. This size only affects the plastic; there are no changes in the chip itself and there cannot be any. You can use regular SIM card(mini-SIM), and if you upgrade your smartphone to a more new model, which requires a micro-sim, you can change it at any time to the desired size, be it micro-sim or nano-sim.

How to cut a SIM card for a nano-SIM?

There are several ways to make a nano-sim from a micro-sim:

First way- this means contacting a specialized store or communication salon of any operator, and in a couple of minutes they will give you the required SIM card size. The cost of this service, as a rule, does not exceed the cost of the starter package/SIM card itself, or is completely free. This service, will definitely be free if you buy starter pack and immediately warn you about what SIM card you need, in which case the operator’s representative must give you the required SIM card size.

Second way- this is to cut the SIM card yourself under the nano-SIM. Be prepared to need a ruler, scissors or a sharp utility knife, and possibly sandpaper. Attention! This method is less preferable, since there is a risk of touching one of the 6 contacts of your SIM card chip, which is why you will need to restore the SIM card by contacting your operator.

So, if you decide to cut the SIM card yourself, then let’s move on directly to cutting:

Remember! Having cut a SIM card, for example, to the size of a nano-SIM, they may still differ in thickness, since the thickness of a nano-SIM card is 0.67mm, while mini-SIM and micro-SIM can be: 0.76-0.84mm.

How to insert a nano-sim into a micro-sim?

Changing the size back from a nano-SIM to a micro-SIM or mini-SIM is much more difficult, because you will need a holder/adapter or “holder” for the SIM card. If you have one, then you will not have any difficulties with changing the size, just insert the chip into required adapter and place it on your smartphone or tablet.

The image shows what an adapter for nano-SIM and micro-SIM should look like, as you can see, there is nothing complicated about it, you just need to buy a holder or save it, after purchasing the SIM card itself, as a rule, multi-SIM cards are sold.

Manufacturers of smartphones and tablets strive to reduce the size and weight of their devices as much as possible in order to make them more stylish, convenient and powerful, so new models have no place for excess and completely unnecessary plastic from SIM cards. Instead, you can reduce the size of the gadget itself or enhance it with other useful functionality: processor, memory, etc.

It is the size of the SIM card tray or slot that determines the required chip size, and this will determine which SIM card you need. As a rule, for smartphones that allow you to simultaneously use 2 or more SIM cards, you need to have a microSIM or nanoSIM.

Also, it is worth mentioning that in lately, manufacturers have begun to increasingly use technology for SIM cards and memory cards, however, this is not always convenient, remember this when.

It is unlikely that in our time there will be a person who has not held a SIM card in his hands at least once in his life. For most, this thing has become as familiar as a toothbrush.

Many people had to repeatedly replace their SIM card with a new one for one reason or another. And, nevertheless, for many it represents “something like that, without which you can’t call on cell phone.”

We will try to determine what a SIM card is in a smartphone, telephone or other mobile device, what functions it performs, as well as what types of it exist.

What is a SIM card

In most cases, it looks like a piece of plastic with contacts on it that allow it to be connected to mobile devices.

The plastic is durable and flexible, but can be easily cut if necessary, which allows, if necessary, to change the card format for installation in modern gadgets.

In addition to its main role as an identifier, a SIM card in a smartphone or telephone can perform a number of other functions: additional functions. For this purpose, the module provides an appropriate amount of memory, although it is very small.

It is worth noting that the phone number is not stored directly in the SIM card memory; instead, the International Mobile Subscriber Identity (IMSI) is recorded there - an international identifier mobile subscriber, with which the number is subsequently associated with the mobile operator.

As a rule, SIM cards have two-level protection against unauthorized use. When you turn on your mobile device, the SIM card is activated after entering a short PIN code.

In the event of a triple entry error, the card is blocked, and unlocking is possible only after entering a long pack code, which is usually stored on the packaging supplied with the subscription package.

In case of several unsuccessful attempts, the SIM card is permanently blocked, and it is no longer possible to unlock it using the user’s means. Some people use SIM cards for which entering a PIN code is not provided.

Information stored in the card memory can be moved to the memory of a mobile device. Since the SIM card memory in a smartphone or even a telephone is only a small fraction of the total, this is a fairly relevant procedure.

What types of SIM cards are there in smartphones and other mobile devices?

Why do device manufacturers go to all these lengths, continually creating problems for users of their products?

As a rule, the justification for such downsizing is the reduction in the size of gadgets, supposedly achieved through a small SIM card.

Whether this is true or not is difficult to say; it is unlikely that the extra millimeter won from plastic can cause a revolution in the weight and size characteristics of the device.

But judging by the available information, the next generation of 5FF SIM cards should already be built-in. In this case, the very idea of ​​​​quickly changing the identification module turns into nothing.

Surely many are not delighted with this marketing policy of gadget manufacturers - but, alas, they are unable to change anything. In the meantime, these manufacturers are inventing ways to create for us additional problems, we will try to solve the current problems.

In particular, we’ll talk about what to do if the SIM card doesn’t fit into your smartphone.

How to change the SIM card size for a smartphone

There you will receive a multi-format card, from which you can easily get a SIM card of the required size, or a ready-made nano-SIM card, if that is what you need.

Obvious disadvantage this method is the need to spend time visiting the office; many simply do not have time to do this. Therefore, people are looking for other solutions to the problem.

Using a special tool, your card will be adjusted to the required standard.

But even in this case, you will again have to go somewhere. And most of us would prefer to find a solution to the problem that would allow us not to leave the house at all and do everything from the comfort of our computer chair.

There is, in fact, such a solution. As a last resort, You can carefully trim the card yourself:

1. To do this, you will need a template downloaded from the Internet and printed on a printer, sharp scissors and fine-grained sandpaper.
2. The cut out template must be glued to the surface of the SIM card in accordance with the location of the contact pad.
3. After this, carefully cut off the excess plastic with scissors and clean the edges with sandpaper.

Although, of course, especially talented individuals are not even capable of such “feats.”

Smartphones with two SIM cards

However, over time, the dimensions of the devices decreased, and in 2009, General Mobile DSTL1 smartphones appeared on the market. They allowed users to use not one, but two SIM cards at once.

True, only one transmitter was provided in the design of the device. This meant that if both SIM cards can work in standby mode, then you can only talk on one of them.

Such devices have found their audience among those who have to make frequent calls on several networks. mobile operators.

In this case, using two SIM cards allows you to avoid increased tariffs when making calls to numbers of other operators. I had to pay for this with slightly increased battery consumption.

With the development of networks mobile internet There is another option for using dual-SIM smartphones. One card is used to make calls, and the second is used to surf the Internet.

In fact, the range similar devices the market is not that big.

Moreover, the bulk of them are products of Chinese companies, such as Huawei or Fly.

However, this subclass of gadgets continues to develop: models have already appeared on the market in which you can use as many as three SIM cards, including models even from such a reputable brand as Samsung, which introduced three years ago Galaxy smartphone Star Trios.

What to do if you lose your SIM card along with your smartphone

In this case, the role of the identifier, as mentioned above, is played by the SIM card. Therefore, if it falls into the hands of criminals, it can become a weapon for causing serious harm.

As soon as you discover that your SIM card has been lost, you must immediately take measures to block it. To do this you should:

• Call the support center or visit the nearest communication center of your provider.
• You must have your passport with you, since blocking is carried out only if the subscriber is reliably identified.
• You may be required additional information, for example, the approximate card balance or the numbers of subscribers to whom you have recently made calls.

• This is done through the customer service center, where an application is filled out.
• After submitting it, a check will be performed, if successfully completed, the employee will inform you when it will be possible to receive a new SIM card.
• Sometimes this is done practically “without leaving the cash register.”
• When you restore the card, not only your subscriber number will be restored, but also all the information stored on the card.

Allegedly, if you have the appropriate software, which can be purchased on the black market, you can create a clone card that will allow a cunning attacker to make calls on behalf of its real owner, receive messages and do all the other things that a SIM card allows.

In reality, there is very little truth in these myths. Indeed, theoretically, creating a map clone is possible.

However, since the late nineties, the overwhelming majority mobile providers took a set of measures that make the use of such clones almost impossible.

So today there is no need to be afraid of evil hackers who can copy your SIM card and steal your hard-earned money.

The danger of hacking your phone via the Internet or wireless interfaces is much more real.

It is worth noting that SIM cards are generally used by all mobile operators to identify subscribers. Thanks to this, any subscriber can easily and quickly change cell phones and tablets without changing their phone number, but simply by moving their SIM card to another phone. There are now several known SIM card form factors: regular and micro-SIM.

All SIM cards include microprocessor with software and IMSI data(international mobile subscriber identifier), serial number, temporary information about the network and services available to the user, as well as some other data (for example, the phone book), access to which can be protected by a PIN code system.

Surprisingly, the SIM cards we are all familiar with are actually called mini-SIM. A full-size SIM card is similar in format to a bank card - their dimensions are exactly the same: 85.6x53.98x0.76 mm . The familiar “SIM cards” that we use in mobile phones, mini-SIM, are “broken out” from such a card. Pay attention to the kit that you purchase when connecting. The size of a standard SIM card from mobile operators is 25x15x0.76 mm.

Micro-SIM is the newest version of the subscriber module, differing from all previous ones in size - 15x12x0.76 mm. It was first discussed back in 1998, but the final version of the form factor was agreed upon only at the end of 2003. The main purpose of creating micro-SIM was the possibility of its use in miniature devices for which regular SIM cards are too large. True, no one specified what kind of devices these could be. Probably some kind of spy stuff.

The launch of mass production of micro-SIM was organized at the instigation of Apple. All of its new devices could only work with miniature SIM cards.

Externally, micro-SIM and regular SIM differ only in size. In principle, To use a regular SIM card in an iPad or iPhone 4G, you just need to carefully cut it to micro-SIM size. It will work just as well as the factory one, and this straightforward "file-finishing" method is suggested as the most simple solution. Now almost all operators in the world and in Russia they change standard cards to micro-SIM for free. To do this, just go to the service office and write a statement.

Meanwhile, not everything is so simple. Despite the complete identity of the chips themselves, the micro-SIM specification provides for a number of new functions that SIM cards of other formats do not have. First of all, we are talking about supporting simultaneous access to the map of several applications via virtual channels. This means that data over the telecom operator's network will be transmitted in parallel streams, rather than sequentially, as was previously the case.

New specifications describe increased security features, in particular, a system for mutual authentication of the card and the cell to which it is connected. This helps prevent IP spoofing - a fairly common method hacker attack, which consists in intercepting the subscriber’s IP address and then using it either to enter secure networks or to replace the real IP address in order to obtain the necessary data on the attacker’s device.

Strengthening security measures can also be considered the emergence hierarchical PIN code system with universal PIN code, application code and local code. By analogy with computer operating systems, the universal code provides full rights system administrator, and everyone else has limited rights to perform certain actions. Obviously, such a measure should prevent not so much accidental damage to data stored on the card (and on the connected device), but rather malicious attacks aimed at gaining control of the terminal, including using unauthorized software.

And finally, the fourth new feature, laid down in the micro-SIM specifications, - support for extended phone book increased volume, allowing you to save second names of subscribers, groups, as well as email addresses on the SIM card.

How to make a micro-SIM from a regular SIM card

The manufacturing technology is very simple. To do this, we will need sharp scissors, a sharpened pencil, and a ruler with millimeter cutoffs. It is worth considering that all work must be carried out extremely carefully and carefully.

Stage No. 1. We measure the length and width of a standard SIM card. The SIM cards in our phones have the following dimensions, mm: 25 x 15 x 0.76. We are required to finish them up to standard micro Sim: 15 x 12 x 0.76. There is no need to focus on the thickness - it is the same for both SIM card standards.

Stage No. 2. Mark the cutting lines. We draw a 15 x 12 mm rectangle around the metal chip and mark the lines with a pencil.
It’s worth noting here that some SIM cards have an enlarged chip - in this case you need to cut it using metal, however, the chances are that the SIM card will survive it about 50/50.

Stage No. 3. Cut with scissors. Slowly cut off the excess plastic on the sides. Women's nail scissors are ideal for this operation - they are quite miniature and at the same time very powerful. After trimming, you need to compare the size of the resulting SIM card with the SIM slot of your iPad or iPhone 4. If the SIM card is larger, carefully cut further with scissors.

After this, your micro-SIM is ready.

For our part, we would like to note once again that MTS, Beeline and MegaFon subscribers can change their regular SIM card to a micro-SIM completely free of charge at customer service centers. With other operators the situation is somewhat more complicated, and here you can use a homemade method of manufacturing micro-SIM

SIM card is a device that is a subscriber identification module. It is an integrated circuit designed to securely store an International Mobile Subscriber Identity (IMSI) number and associated key, which are used to identify and authenticate subscribers to devices mobile telephony(eg mobile phones and computers). In addition, you can store contact information on many SIM cards.

SIM cards are always used on GSM phones, for CDMA devices they are only required for new LTE-compatible devices. They can also be used in satellite phones.

The SIM card is part of a universal feature (UICC), which is usually made of PVC with built-in contacts and semiconductors. A SIM card, the device of which is based on digital technology, can transfer data between different mobile devices.

SIM card contains:

• unique (ICCID);
• international mobile phone number (IMSI);
• authentication and encryption;
• temporary information about the local network;
• a list of services to which the user has access;
• The phone's SIM card device also has two passwords: personal identification number(PIN) for normal use and personal code Unlock (PUK) to unlock the PIN code.

History and market entry

The SIM format was originally defined by the European Telecommunications Standards Institute in specification number TS 11.11, which describes the physical and logical properties of a SIM card. With the development of UMTS, specification work was partially transferred to 3GPP.

The first SIM card was developed in 1991 by the Munich smart card manufacturer Giesecke & Devrient, which sold the first 300 copies to the Finnish operator wireless network Radiolinja.

Inactivation

In many pay-as-you-go contractual agreements, you need to periodically use prepayments to avoid expiration account. This period depends on the network operators, but is usually defined as a period of three months. This is sometimes due to the SIM card becoming inactive on the network.

Registration

Most countries and operators require identification to activate the service, but there are some exceptions such as Hong Kong SAR.

How does a phone's SIM card work?

There are three operating voltages for SIM cards: 5 V, 3 V and 1.8 V. The operating voltage of most SIM cards launched before 1998 was 5 V. Subsequently created cards are compatible with 3 V and 5 V. Modern copies support voltage 5 V, 3 V and 1.8 V.

Data

SIM cards store network information used to authenticate and identify subscribers on the network. The most important ones are ICCID, IMSI, authentication key (Ki), local area identifier (LAI) and operator number.

The SIM card, whose design is based on circuits, also stores other operator-specific data such as the service center number short messages(SMS ServiceServiceName), Service Provider Name (SPN), Service Number Numbers (SDN), Advanceofcharge parameters and Value Added Applications (VAS).

SIM cards can be supplied in varying data sizes from 8 to at least 256 KB. They all allow you to store a maximum of 250 contacts, but while the 32KB version has room for 33 Mobile Network Codes (MNCs) or "network identifiers", the 64KB variety has room for 80 MNCs. This metric is used by network operators to store information about preferred networks and is mainly used when the SIM is roaming rather than on its home network. What does this phone SIM card device mean?

The operator who issued the SIM can use this to connect the phone to their preferred network to take advantage of the best commercial deal for the original network company. This does not mean that a phone containing this SIM can connect to a maximum of 33 or 80 networks, only that the SIM card issuer can only specify up to that many preferred networks. If the SIM is outside of these preferred networks, it will use the first or best available one.

ICCID

Each SIM card is identified internationally by ID integrated circuit(ICCID). ICCIDs are stored on SIM cards and are also engraved or printed on the case during the personalization process.

The ICCID is defined by ITU-T Recommendation E.118 as the Primary Number. Its layout is based on ISO/IEC 7812. According to E.118, the number can be up to 22 digits, including one check digit calculated using the Luhn algorithm. However, GSM Phase 1 defined the ICCID length as 10 octets (20 digits) with a specific operator structure.

International Mobile Subscriber Identity (IMSI)

SIM cards are identified within individual operator networks using a unique International Mobile Subscriber Identity (IMSI). Operators connect to mobile phone calls and exchange their SIM cards in the market using their IMSIs. Their format is as follows.

The first three digits represent mobile code countries (MCC).

The next two or three digits represent the code mobile network(MNC). Three-digit MNC codes are allowed by E.212 but are primarily used in the United States and Canada.

The following digits represent the Mobile Subscriber Identification Number (MSIN). Typically this is 10 digits, but the value will be less in the case of a three-digit MNC or if national regulations specify that the total length of the IMSI must be less than 15 digits. All these numbers differ from country to country, so there may be differences in how the SIM card is designed. The circuit is standard and factory-made, the difference is only observed in the recorded information.

Authentication Key (Ki)

Kni is a 128-bit value used to authenticate SIM cards on the GSM mobile network (for the USIM network you still need Ki, but different parameters are required). Each SIM card stores a unique Ki assigned to it by the operator during the personalization process. This setting is also stored in a database (called an authentication center, or AuC) on the carrier's network.

How is a SIM card designed taking into account the above? It is designed to prevent Ki from being obtained through the smart card interface. Instead, the SIM card provides a "Run GSM Algorithm" feature that allows the phone to transfer data to the SIM card, which must be signed with Ki. This in theory makes the use of a SIM card mandatory if Ki cannot be removed from the SIM card or the operator wishes to disclose this option. In practice, the GSM cryptographic algorithm for calculating SRES_2 (see step 4 below) from Ki has certain vulnerabilities that could allow this value to be extracted from the SIM card and create a duplicate SIM card.

Authentication process

When the mobile equipment starts up, it obtains the International Mobile Subscriber Identity (IMSI) from the SIM card and passes it to the mobile operator, requesting access and authentication. Mobile equipment can transmit a PIN code to the SIM card before it reveals this information.

Location Area Identification

The SIM stores network status information, which is received from the Location Area Identifier (LAI). Operator networks are divided into location areas, each of which has a unique LAI number. When the device changes location, it stores the new LAI on the SIM card and sends it back to the carrier network with the new location. If the device is running cyclically, it will retrieve data from the SIM card and search for the previous LAI. Some listening devices with a SIM card also work on this feature.

SMS messages and contacts

Most SIM cards will by default store a number of SMS messages and phonebook contacts. Contacts are stored in simple pairs"name and number": Records containing multiple phone numbers and additional phone numbers are usually not stored there. Such conditions are provided by the SIM card device. Contacts can be saved to a very limited extent. For example, when a user tries to copy such records to a SIM card, software phone number splits them into multiple entries, discarding any information that is not a phone number.

The number of saved contacts and messages depends on the SIM card. Early models will only store five messages and 20 contacts, while modern SIM cards can typically store more than 250 items.

SIM card: device and formats

Over the years, SIM cards have become smaller, and their functionality does not depend on the format. The full-size SIM card was followed by mini-SIM, micro-SIM and nano-SIM. Today they even come built into devices.

Full-size SIM card

The full-size SIM card (or 1FF, 1st form factor) became the first form factor. She has the size credit card(85.60 × 53.98 × 0.76 mm). Later, smaller SIM cards were often sold built into a full-size card from which they could be ejected.

Mini-SIM

A mini-SIM (or 2FF) card has the same contact arrangement as a full-size SIM card and usually comes in a full-size adapter with connectors attached to it. This scheme allows it to be used both in a device that requires a full-size card, and in a device that requires a mini-SIM card (after breaking the connecting elements). Since the full-size SIM card is no longer used, some vendors refer to this form factor as a standard or regular SIM card.

Micro-SIM

A micro-SIM (or 3FF) card has a similar thickness and pin layout, but is distinguished by a reduced length and width.

The micro-SIM format was introduced by the European Telecommunications Standards Institute (ETSI) for installation in devices too small for a mini-SIM card. The form factor was mentioned in the 3GPP SMG9 UMTS working group, which is the standards-setting body for GSM SIM cards, in December 1998, and subsequently agreed upon in late 2003.

Micro-SIM was developed for the main problem was the contact area of ​​the chip. Maintaining the same contact area allows the micro SIM to be compatible with previous, larger SIM card readers through the use of plastic cutouts. The device has also been designed to operate at the same speed (5 MHz) as the previous version. The same pin sizes and positions have led to numerous tutorials and YouTube videos with detailed instructions, how to cut a mini-SIM card to micro-SIM size. However, such actions at home sometimes lead to the fact that the SIM card does not correspond to the device or becomes completely unusable.

Nano-SIM

The nano-SIM (or 4FF) card was introduced on October 11, 2012, when suppliers mobile services V different countries started shipping it for phones that support this format. The Nano-SIM measures 12.3 x 8.8 x 0.67 mm and reduces the previous format to just the contact area while retaining existing features. A small rim of insulating material is left around the contact area to avoid short circuits. The Nano-SIM is 0.67mm thick compared to its predecessors' 0.76mm. 4FF cards can be placed in adapters for use with devices designed for 2FF or 3FF SIM cards and made thinner to do so, but many phone companies do not recommend this.

The iPhone 5, released in September 2012, was the first device to use activated SIM cards nano, followed by other phones.

The upcoming new generation of SIM cards is called e-SIM or eSIM (embeddedSIM), which is a non-replaceable built-in chip in a SON-8 package - soldered directly onto the circuit board. It will have M2M capabilities and remote access to the SIM card.

Story

In 1G networks, subscriber identification on the network was carried out by serial number cell phone- ESN (Electronic Serial Number). Thus, both the cell phone and the subscriber were identified with a single code. This approach generated complete dependence of the subscriber’s number and the package of services provided to him on a specific telephone instance. Having changed a cell phone (including cases of breakdown and theft of the phone), the subscriber was forced to contact the operator’s office in order to have the phone reprogrammed and its serial number entered into the operator’s database, which some operators did for a fee.

Obviously, subscriber identification independent of the phone is more convenient. In the GSM standard, it was proposed to separate the identification of the subscriber (using a SIM card) and equipment [for this, IMEI (International Mobile Equipment Identifier) ​​is used International identifier mobile equipment)].

Standards

GSM SIM card is a type of regular ISO 7816 smart card. The standard for the specific features of the card for GSM SIM is established by documents GSM 11.11, GSM 11.14 and GSM 11.19. Modern maps have the ability to run applications on the card, and therefore support JavaCard functionality.

Features and Specifications

The main function of a SIM card is to store account identification information, which allows the subscriber to easily and quickly change cellular devices without changing his account, but simply by moving his SIM card to another phone. To do this, the SIM card includes a microprocessor with software and data with card identification keys (IMSI, etc.), written to the card at the stage of its production, used at the stage of card (and subscriber) identification by the GSM network.

The SIM card can also store additional information, such as the subscriber’s phone book, lists of incoming/outgoing phone numbers, and the text of SMS messages. IN modern phones, especially smartphones, this data is not written to the SIM card, but is stored in the phone’s memory, since the SIM card imposes fairly strict restrictions on the format and volume of data stored on it.

The SIM card contains a memory chip that supports encryption. There are cards of different standards, with different sizes memory and different functionality. There are cards on which they are installed during production additional applications(applets) such as SIM menu, telebanking clients, etc.

The subscriber's telephone number (MSISDN) is not explicitly stored on the card itself; it is assigned network equipment operator when registering a SIM card in the network based on its IMSI. According to the standard, when registering one SIM card in the network, the operator can assign several phone numbers to it. However, this feature requires appropriate support from the operator’s infrastructure (and corresponding costs on its part), so it is most often not used.

If a SIM card is lost, the subscriber must notify the operator, the lost card is blocked, and the subscriber is issued a new card (paid or free, depending on the operator’s conditions). The phone number, balance and all connected services remain unchanged, but all subscriber data stored on the SIM card cannot be restored.

The SIM card fits into the cell phone's SIM holder, which is usually located under the battery in modern cell phones. The location of the SIM holder under the battery does not allow you to install/remove the SIM card when the phone is powered on, because this may damage the card.

SIM card sizes

• Full-size SIM card (86x54x0.84 mm) - an outdated standard, used in the first cell phones (about the size of a credit card);
• Mini-SIM card (25x15x0.76 mm) - widely used now in GSM phones and in most 3G phones;
• Micro-SIM card (15x12x0.76 mm) - used in new models with 3G (Apple iPad and iPhone 4, Nokia N9, all models of the Nokia Lumia line, LG U880, Samsung Galaxy S III and some others)
• Nano-SIM card - There are 3 versions of Nano-SIM:
  1. (12x9 mm) Developed by en: Giesecke & Devrient with the participation of Apple. The thickness is reduced by about 15% compared to others. Backward compatibility is achieved using an adapter.
  2. (10x8) Nano-SIM variant proposed by Nokia, which is something similar to an SD card. The advantage is that the card does not require a special tray, and therefore there is more space in the device itself, which can be used, for example, to increase the size of the battery. Unfortunately, this card can only be used in new devices with a special output.
  3. (11x9) Nano-SIM proposed by RIM. Similar to Nokia's Nano-SIM, differing only in size.

Standardization of the Nano SIM format should be completed by the European Telecommunications Standards Institute (ETSI) before the end of 2011, and the first phones with the corresponding connectors should appear on sale in 2012. As of June 5, 2012, Nano-SIM dimensions were approved: length - 12.3 mm, width - 8.8 mm, and thickness - 0.67 mm. The official nano-SIM standard will be fully compatible with previous versions. Essentially, the new SIM card is the same as a micro-sim, only with the plastic edges removed. When making a decision, experts considered that Apple’s offer was the most convenient and simple.

• Virtual SIM card - patent pending by Apple.

SIM cards are usually produced as full-size cards, allowing them to be used in older standard phones. For use in modern phones, it is provided that the Mini/Micro-SIM module can be removed (“broken”) from a full-size card once.

Micro-SIM

Micro-SIM- an updated and miniature SIM card alternative for identifying subscribers on mobile devices. The physical size of the card is 12 x 15 mm. Micro-SIM is smaller than the mini-SIM used in mobile devices, but the contact plate and communication interface are usually identical. Therefore, in most cases, you can get a micro-SIM from a mini-SIM by cutting the plastic case.

Multi-SIM cards

Multi-SIM cards ( "MultiSim") - devices in the form of a regular SIM card (GSM standard) and consisting of a microprocessor (PIC-processor PIC16F877) and additional module memory (24C64 - 24C256). The microprocessor operates under the control of a special firmware (SIM-EMU 6.01), which in addition performs the functions of a regular SIM card. This concept makes it possible to record the data you need from several SIM cards at once into the MultiSim card and use the number that is most convenient at the moment. You can select the desired number in special menu(using technology "SIM Tool Kit") or when entering the PIN code of the number you need.

PIN code

When a SIM card is issued, it is assigned a four-digit digital PIN code, which is recorded on the card and also sent to the subscriber along with the card. The PIN code is requested by the phone every time it is turned on in order to access the data on the SIM card. Typically, the SIM card allows you to disable PIN code verification when you turn on the phone. After this, all SIM card functions become available immediately after turning on and booting the phone.

If the PIN code is entered incorrectly three times in a row, the card is blocked and can only be unlocked by entering the personal unlock code PUK1, which is also transmitted to the subscriber along with the card. If the PUK code cannot be entered correctly after ten attempts, the SIM card is completely blocked and must be replaced.

If a SIM card is not installed in the phone, or if the correct PIN code is not entered, the phone cannot make any calls to cellular network except for the call emergency services(number 112 or 911). All other functions on most phones are usually blocked (this does not apply to smartphones and communicators).

ICCID

ICCID- (English) Integrated Circuit Card Id). Usually this is the code printed on the SIM card. The ICCID is defined according to the ITU-T E.118 standard. According to this standard, the ICCID length is 19 digits:

• 2 digits - Major Industry Identifier(industry identifier, per ISO/IEC 7812-1), for SIM cards always 89 ;
• 1-3 digits - dialing code countries (via E.164), 7 for Russia, 380 for Ukraine, etc.;
• 2-4 digits - issuer code (the total length of this and the previous fields cannot exceed 5 digits);
• 11 digits - determined by the operator when producing the card according to internal rules;
• 1st digit (last) - check digit calculated using the Luna algorithm.

The first 7 digits of the ICC ID are generally called Issuer Identification Number, and are issued by the ITU to each telecom operator that plans to issue SIM cards.

SIM Tool Kit

Modern SIM cards may come pre-installed with applications provided by the operator. To use applications on a SIM card, your phone must support the SIM Tool Kit (STK) standard. Applications on the SIM card using STK can use various functions cell phone, including user interface, communication module, etc., which allows you to implement a fairly wide range of functionality. STK applications are under the full control of the operator and are considered the most secure, as they can use the encryption module built into the card, which makes them extremely attractive for the implementation of financial services, such as telebanking or payment authentication. It is also possible for the operator to download and update these applications directly using the cellular network. The disadvantage of such applications is that their use requires issuing a card that supports the SIM Tool Kit with sufficient memory and transferring it to the subscriber, which is quite difficult from an organizational point of view.

STK is often used to implement the SIM menu service, which is available for most Russian operators. To interact with the operator, this application uses SMS, USSD or CB messages hidden from the subscriber.

Notes

See also

• A Key
• Terminal account
• MultiSIM

Links