Mifare® - NXP® cards

Mifare^® is the NXP^® Semiconductors trademark of a series of chips widely used in contactless smart cards and proximity cards.

Mifare^® tehnology is a 13.56 MHz contactless technology (ISO 14443) used in the production of different memory cards and readers for everyday use. This technology is often called the Smart Card technology.

The typical read-range on a Mifare^® contactless smart card reader is 2,5 cm to 10 cm (1.0” to 3,9”).

The standard Mifare^® card is factory programmed with a unique 32-bit serial number.

A smart card is a standard-sized plastic card with an embedded integrated circuit chip which has memory and/or microprocessor functionality.

Mifare^® card memory is divided into sectors and blocks. By type, the classic Mifare^® card can have a memory size of 1024 bytes (1K) which is divided into 16 sectors that are protected with two different keys, A and B or the memory of 4096 bytes (4K) divided in 40 sectors of which the size of 32 sectors as 1K while the remaining eight sectors are  fourfold larger. There is a also Mifare^® cards with 320 bytes of memory divided into 5 sectors. For each of these card types, 16 bytes per sector are reserved for the keys and access conditions and can not normally be used for user data. Also, the very first 16 bytes contain the serial number of the card and certain other manufacturer data and are read only. The remainder of the memory capacity is available for entry of desired data.

The most commonly used Mifare^® card is a 1K card and we will just pay more attention to its performance.

The Mifare^® card has 16 separate sectors, which can be configured as purses or for general data storage. The first sector is typically used as a directory for the rest of the card, leaving 15 segments available for data or purses.

This card is designed to allow you to embed an optional contact smart chip modules, if done, this card would be ISO 7816 compliant as well. This card is designed to have a magnetic stripe on the card. In this configuration, this card would be ISO 7811 compliant as well.

Mifare^® technology does allow for mutual authentication between the card and reader.

The RF data transmission between the mifare^® card and reader is encrypted while the data stored on the card might or might not be encrypted in which case the security could be provided by defining the proper keys.

Mifare^® Standard ISO 14443 is divided into two types (Type A and Type B) and in four parts.

ISO 1443 Tip A (ISO 14443A) contactless card was originally intended to be a memory card only. However, microprocessor and cryptographic cards have been developed for Type A. The most common Type A cards are referred to as Mifare^® cards

ISO 1443 Tip B (ISO 14443B) contactless card was originally intended to be microprocessor version of Type A. Again, the memory and cryptographic options have been added for Type B thereby creating competition between Type A and Type B cards. The Type B cards are not as commonly deployed as Type A cards.

Type A and Type B contains four parts and the difference between this two types is in the method of modulation (coding scheme - second part, the procedures protocols initialization at part 3 while in the 4-part both types are using the same transfer protocol).

ISO/IEC 14443-1 – Identification cards - Contactless integrated circuit cards - Proximity cards - Physical characteristics

ISO/IEC 14443-2 - Identification cards - Contactless integrated circuit(s) cards - Proximity cards - Radio frequency power and signal interface

ISO/IEC 14443-3 - Identification cards - Contactless integrated circuit(s) cards - Proximity cards - Initialization and anticollision

ISO/IEC 14443-4 - Identification cards - Contactless integrated circuit cards - Proximity cards - Transmission protocol.

Mifare^® DESFire is another NXP^® microprocessor platform, based on a similar core as SmartMX, with more hardware and software security features than the standard MIFARE Classic chips. It is sold already programmed with a general purpose software (the Mifare^® DESFire operating system) that offers a simple directory structure with files, similar to what is typically found on smart cards.

Using DES encryption for all data traffic, Mifare^® DESFire adds higher security for the applications. Another unique feature of DESFire is a flexible file system that allows more efficient use of 4K memory card. One DESFire card may contain data of 28 different applications. Each application may contain 14 files, each file has its own security key.