This article once again addresses the issue of radio frequency identification technology, and addresses one of the most common standards in USA today.
The RFID theme, as we have said, is limitless. Today we will focus on a detailed review of another standard that is widely used in everyday life - the Philips Semiconductor Mifare® standard. Millions of people are already using this standard in NY...
Mifare® is an RFID object identification system with a reading and writing distance of up to 10 cm and conforming to ISO / IEC 14443, type A. It has an anticollision algorithm and allows simultaneous work with several cards in the reader field. Mifare® microchips are convenient for use in cards and various forms of transponders, which can be made in the form of key chains, coins, bracelets, etc. Consideration of the Mifare® architecture will start with the most common modification - Mifare® Standard. Map data structure The table shows the internal data structure of the map (sectors 2 through 13 are not shown - they are identical to the others).
The entire memory of the card is divided into 16 sectors of equal size of 64 bytes each. In turn, each sector is divided into 4 blocks, with the last block of each sector containing keys and access rules to the sector, which allows using the card in 16 different non-overlapping applications. Due to the fact that each application “knows” only its own access keys, the other sectors of the map are not accessible to it. The assignment of keys for each sector determines the access bits, which makes it possible to separate read and write permissions for different subjects, even within the same application.
Data blocks can be of two types - standard data blocks and the so-called value - blocks that have a fixed format and are intended to use the sector as an "electronic wallet".
The zero sector differs from the others in that it contains only two data blocks. Zero sector zero block contains service information recorded during production - the card's serial number (4 bytes) and the manufacturer's data. Access to the zero block is always open for reading, while all other blocks require access to (even for reading) knowledge of the access keys.
As can be seen from table 1, the net information capacity of a standard card is 752 bytes, which is substantially more than all other known rewritable contactless cards. In addition to Mifare® Standard (versions with 1 and 4 kilobyte memory), Mifare® UltraLight and Mifare® ProX cards are currently being produced. The first is a very simplified version of the standard card with less memory and no cryptographic protection of the radio channel. It is intended mainly for single tickets, made in the form of a cardboard card and has an extremely low price. In contrast, Mifare® ProX is a card with significantly expanded randomly configurable memory (up to 16 kilobytes), an integrated microcontroller based on the Intel 80С51 core and advanced cryptographic protection mechanisms. In addition, this card has two interfaces: a radio channel and a standard one for smart cards - a contact one, which allowed certifying it as a payment card for use in banking systems instead of magnetic stripe cards, which should soon cease to exist.
The main characteristics of Mifare® cards are listed in Table 2. For Mifare® ProX, only two (minimum and maximum) of the four types that exist today are given.
Mifare® is an open platform available for the development and production of devices in any companies with relevant experience. Mifare® support for system integrators, card makers and readers, and software developers is provided through the Testhouse Arsenal Mifare® Certification Institute (MCI). A list of all companies operating in the MIFARE standard can be found in the Mifare® Book of Partners document, and the exchange of information is possible through the Mifare® Association - a forum for the promotion and support of products being developed.
Areas of use
The main use for the Mifare® family is e-tickets for public transport. For example, in the Moscow metro, passengers simply bring their card to the reader and pass through the turnstile. With different keys, Mifare® cards can be configured for use in several applications, for example, paying for various types of transport, parking, at gas stations.
A large-scale project based on the MIFARE technology has been implemented and developed in the Moscow region. Originally conceived as a method of collecting payments in the metro for long-term travel documents, this project is currently being implemented as the basis for creating a unified city payment system.
The new project, launched in 2001 - “Social Card of Muscovite” in accordance with the order of the Government of Moscow dated August 7, 2001 N 715-RP “On conducting an experiment on the introduction of the Social Card of Muscovite into operation” should open the way to the widespread introduction of technology MIFARE. Trial operation in areas of Moscow such as Chertanovo Tsentralnoye, Chertanovo Yuzhnoye and Biryulyovo West was recognized as successful.
Another large project is the universal student card (Figure 1), which combines the functions of a student ticket, a standard Moscow Metro transport card and a bank card of the STB payment system.
At present, over 3 million MIFARE cards have been issued in the Moscow region, which are used in the following applications:
Travel document of the Moscow metro
Travel document of the Moscow Railway
Student transport card
Student transport card with bank application
Certificate of Advisor to the District Assembly
Moscow student card
Muscovite social map
We can say that Mifare® cards are the best solution for the integrated provision of services at enterprises, in educational institutions, clubs, sports complexes and resorts.
Perspectives of the standard
The Mifare® standard has a “long life” due to its wide penetration into many areas of people's daily activities. One can hardly expect that in the near future some other technology will force out Mifare® from the above-mentioned applications, since the cost of providing the infrastructure for working with cards amounts to billions of dollars. Rather, it will not be the replacement of this standard with something else, but its further development. And the first sign of such an evolution is already taking place.
If in Europe, the Mifare® card from Philips Semicondactors is ubiquitous, in Southeast Asia (Japan, Singapore, China) the Sony FeliCa card is more common. As of June 2002, 12 million FeliCa cards were issued in Hong Kong, while the entire population of this area is 6.85 million people.
The main areas of application of the FeliCa and Mifare® cards are similar: they are access control to the buildings, personnel identification, pay for telephone calls and public transport. But until now, to use FeliCa and Mifare® cards, two different reading devices were needed - plastic cards with Sony and Philips Semicondactors processors were incompatible.
And recently, Philips Semicondactors and Sony signed an agreement on joint development and marketing of a new generation of contactless smart cards - NFC. The NFC technology being developed by these two companies should eliminate the incompatibility problem, and not only bring together the existing developments of both companies in this area, but also allow the creation of fundamentally new ways of remote access to information and services.
Since the subject of the journal is related to the security industry, the reader would like to understand how the implementation of the Mifare® standard in everyday life will also affect the security industry? The answer to this question is the following: if the majority of the population of Moscow and the region will soon become owners of a universal contactless plastic card, is it not logical to use it in access control systems? After all, besides the fact that the card is already in the hands of the majority of the population, it can be offered to those who do not already have it, and at a very competitive price! Despite the fact that the Mifare® card is more complicated than the standard cards used in access systems, its cost has recently become quite comparable to the cost of simpler cards due to mass emission.
Suffice it to recall that the world leader in proximity card and reader production has not been the first for HID to produce readers for access systems that support the Mifare® format
The objective need to improve the security of educational institutions leads to the fact that access control systems are gradually being introduced in universities and schools. And here, when choosing a type of card, there are no alternatives - if each student has such a card in his hands, then it is logical to use it and only use it to access schools and institutes. The system of factory numbering of cards ensures their uniqueness by serial number, which is necessary for unique identification of the owner.
If you go further, it becomes clear that the integrated system of the school or the university will allow you to implement attendance accounting, internal cashless payments (for example, in the school canteen), organize the service in the library, etc, on the basis of such a card. d.
In the near future, most likely, only the card’s serial number will be used for access systems. A reader oriented to these applications must be compatible with standard controllers, that is, support, first of all, the Wiegand format. Other use cases are complicated today by the fact that almost none of the access control system controllers support two-way communication with readers, which, in turn, does not allow the use of a protected area of the card and the write-read mode. But this fact does not pose a serious problem for the widespread introduction of this type of cards in security systems.
Since we are talking about using Mifare® cards in access systems, we need to mention another solution based on these cards. Recently, there has been an intensive growth in the use of biometric technologies in access systems, in particular, human fingerprint recognition. There is also one barrier connected with the fact that the amount of information extracted from the scanned print is hundreds of bytes. The access controllers now being produced, firstly, are not designed to receive this amount of information from the reader, and, secondly, they do not have built-in fingerprint verification functions. The rapid introduction of biometric technologies has become possible due to “half-hearted” solutions, when the reader performs verification of human signs, and only the user's identification code is transferred to the controller in that Wiegand format. One solution is that the fingerprint sample is stored in the card and read from it along with the identification number. Then the reader scans the finger, compares the result with that read from the card, and if the result is positive, sends the user code to the controller. So, of the rewritable contactless cards today, only Mifare® has enough memory to store not even one, but several fingerprints. In Figure 3 you can see a biometric reader.
V-Smart manufactured by Biosrypt (USA), which implements this principle.
Bioscrypt Mifare® Card Reader and V-Smart Fingerprint Reader
This article concludes with a brief overview of RFID technology. Of course, the author by no means claims the completeness and unambiguity of the stated facts and approaches to the problem. At the same time, we hope that this cycle of articles has created for readers a general idea of such a fairly promising today direction as radio frequency identification.