RFID Vs Contactless Smart cards

The debate between RFID and smart cards technology is an ongoing one. There is no clear definition that describes RFID and smart cards, and at times these two terms are used interchangeably, due to lack of awareness, resulting in confusion between the differences.

Confusion is especially strong between contactless smart cards and RFID. The key issue that has given rise to this debate is the contact less interface and that too an RF (radio frequency) one. Both contactless smart cards and RFID use radio frequencies for communicating between the card and reader. The applications for which RF is used can be different for RFID and smartcards. RFID is mainly meant for applications within the supply chain, for track and trace. Contactless smart cards on the other hand are mainly meant for payments/banking, mass transit, government and ID, and access control.

RFID and smart cards both can be used in transit applications and most of the time they are used together to provide increased convenience to end users. An example of this would be the “Touch n go” cards in Malaysia used on toll ways. The Touch n Go card is a contactless smart card, but this card can be purchased with an additional RFID transponder (where the smart card will be inserted) so that the toll booth reader can read the cards from a greater distance than the 10cm limit restricted by smart card standards. Without the additional RFID transponder, the contactless Touch n Go smart cards can still be used, which means that the driver need to screen down their windshield to tap the card on the reader, instead of just driving through while the RFID transponder will be detected by the reader above the toll booths at a greater distance.

A brief introudction of RFID standards

A brief introudction of RFID standards
Standards are crucial for many RFID applications, for example payment systems and tracking goods or reusable containers in open supply chains. A great deal of work has been happening in the last decade to build up standards for different RFID frequencies and applications.

There are existing and proposed RFID standards that cope with the air interface protocol (the way tags and readers communicate), data content (the way in which data is organized or formatted), conformance (methods to test that products satisfy the standard) and applications (how standards are utilized on shipping labels, for example).

The International Organization for Standardization (ISO) has established standards for tracking cattle with RFID. ISO 11784 defines how data is structured around the tag. ISO 11785 defines the air interface protocol. ISO has created a standard for the air interface protocol for RFID tags used in payment systems and contactless smart cards (ISO 14443) and in vicinity cards (ISO 15693). It also has established standards for testing the conformance of RFID tags and readers to a standard (ISO 18047), and for testing the performance of RFID tags and readers (ISO 18046).
Using RFID to track goods in open supply chains is relatively new and much less standards happen to be finalized. ISO has proposed standards for tracking 40-foot shipping containers, pallets, transport units, cases and different items. These are at various stages in the approval process.

The conventional situation was complicated because the Auto-ID Center, which developed Electronic Product Code technologies, chose to create its own air interface protocol for tracking goods through the international supply chain. This short article explains the evolution from the Electronic Product Code and also the importance of various ISO standards.

The Auto-ID Center was placed in 1999 to develop the Electronic Product Code and related technologies that could be used to identify products and track them through the global logistics. Its mission ended up being to create a low-cost RFID system, because the tags must be disposable (a manufacturer putting tags on products shipped to some retailer never was going to get those tags back to reuse them). It had to operate in the ultra-high frequency band, since UHF delivered the read range needed for supply chain applications, such as reading pallets coming through a dock door.
The Auto-ID Center also wanted its RFID system to become global and to depend on open standards. It needed to be global because the aim was to utilize it to track goods as they flowed from the manufacturer in one country or region to companies in other regions and eventually to store shelves. For Company A to see a tag placed on an item by Company B, the tag needed to make use of a standardized air interface protocol. The Auto-ID Center developed its own protocol and licensed it to EPCglobal on the condition that it would be provided royalty-free to manufacturers and end users.

The center also was charged with creating a network architecture?aa layer integrated using the Internet?athat would enable one to look up information of a serial number stored on the tag. The network, too, must be according to open standards utilized on the web, so companies could share information easily and also at low cost.

One option the Auto-ID Center had was to get the numbering system and network infrastructure and employ ISO protocols because the standard for that air interface. Earlier, EAN International and the Uniform Code Council had merged their efforts to produce the Global Tag (GTAG), with ISO’s UHF protocol. But the Auto-ID Center rejected this, since the ISO UHF protocol was too complex and would increase the cost of the tag unnecessarily.

The Auto-ID Center developed its very own UHF protocol. Originally, the center planned to possess one protocol that may be used to contact different classes of tags. Each successive type of tags would be more sophisticated compared to one below it. The classes changed with time, but here’s what was originally proposed.

Class 1: a simple, passive, read-only backscatter tag with one-time, field-programmable non-volatile memory.
Class 2: a passive backscatter tag with as many as 65 KB of read-write memory.
Class 3: a semi-passive backscatter tag, with up to 65 KB read-write memory; essentially, a category 2 tag having a built-in battery to aid increased read range.
Class 4: an energetic tag that uses a built-in battery to run the microchip’s circuitry and also to power a transmitter that broadcasts an indication to some reader.
Class 5: an active RFID tag that can communicate with other Class 5 tags and/or other devices.

Eventually, the Auto-ID Center adopted a Class 0 tag, that was a read-only tag which was programmed at the time the microchip is made. The Class 0 tag used another protocol in the Class 1 tag, which meant that end users needed to buy multiprotocol readers to see both Class 1 and Class 0 tags.
In 2003, the Auto-ID Center transitioned into two separate organizations. Auto-ID Labs at MIT along with other universities around the world continued primary research on EPC technologies. EPC technology was licensed towards the Uniform Code Council, which set up EPCglobal like a partnership with EAN International, to commercialize EPC technology. In September 2003, the Auto-ID Center handed off the Class 0 and Class 1 protocols to EPCglobal, and EPCglobal’s board subsequently approved Class 0 and Class 1 as EPC standards.
Class 1 and sophistication 0 have a handful of shortcomings, in addition to the fact that they are not interoperable. One issue is that they are incompatible with ISO standards. EPCglobal could publish them to ISO for approval as an international standard, but it’s likely that ISO would want to revise them to bring them into line with ISO RFID standards. Another issue is that they cannot be used globally. Class 0, for example, sends out an indication at one frequency and gets to be a signal back at a different frequency inside the UHF band; this really is prohibited in Europe, based on some experts (European Union regulations are open to interpretation).

In 2004, EPCglobal began creating a second-generation protocol (Gen 2), which may not be backward suitable for either Class 1 or Class 0. The aim ended up being to create a single, global standard that would be more closely aligned with ISO standards. Gen 2 was approved in December 2004. RFID vendors which had done the ISO UHF standard also done Gen 2. –
Gen 2 was designed to be fast-tracked within ISO, but a final minute disagreement over something called an Application Family Identifier (AFI) is likely to slow ISO approval. All ISO RFID standards come with an AFI, an 8-bit code that identifies the origin of the data on the tag. Gen 2 has an 8-bit block of code you can use to have an AFI, but it’s not necessary underneath the standard. (Requiring the eight bits to be used to have an ISO AFI might have limited EPCglobal’s treatments for EPCs.) But vendors are making product in line with the new Gen 2 standard, which makes way for global adoption of EPC technology in the supply chain.

ISO Standards
ISO has developed RFID standards for automatic identification and item management. This standard, referred to as ISO 18000 series, covers the air interface protocol for systems apt to be used to track goods within the logistics. They cover the major frequencies used in RFID systems around the world. The seven parts are:
18000 C1: Generic parameters for air interfaces for globally accepted frequencies
18000 C2: Air interface for 135 KHz
18000 C3: Air interface for 13.56 MHz
18000 C4: Air interface for just two.45 GHz
18000 C5: Air interface for five.8 GHz
18000 C6: Air interface for 860 MHz to 930 MHz
18000 C7: Air interface at 433.92 MHz

EPCglobal’s Gen 2 standard might be submitted to ISO under 18000-6, but it’s unclear when which will happen or how fast it will be approved. ISO slowed approval of 18000-6 to ascertain if it may be aligned with Gen 2. EPCglobal provides a committee to try and resolve the issue. Requiring an AFI would require dealing with a formal procedure for amending the EPC standard. Customers would like there to become one international standard for tracking goods with the open logistics using UHF RFID tags. But it might take another year before that finally happens.

NFC

Using NFC data is exchanged by two inductively coupled coils — one per appliance — generating an magnetic field with a frequency of 13.56 MHz. The field is modulated to facilitate data transfers. For the communication one device acts as the initiator (starting the communication) whereas the other device operates in target mode (waiting for the initiator). Thus not more than two devices can be evolved in the communication.
The rolls of the devices — initiator and target — are assigned automatically during the listen-before-task concept which is part of the mode switching of NFC. In general each NFC device acts in target mode. Periodically the device switches into initiator mode in order to scan the environment for NFC targets (= polling) and then falls back into target mode. If the initiator finds a target an initiation sequence is submitted to establish the communication and then starts exchanging data.
NFC distinguishes two operation modes for communication: passive and active mode.
Passive Mode
In passive mode only the device that starts the communication (the initiator) produces the 13.56 MHz carrier field. A target introduced to this field may use it to draw energy but must not generate a carrier field at its own. The initiator transfers data by directly modulating the field, the target by load-modulating it. In both directions the coding complies with ISO14443 or FeLiCa, respectively. This mode enables NFC-devices to communicate with existing contactless smart cards. The term load modulation describes the influence of load changes on the initiator’s carrier field’s amplitude. These changes can be perceived as information by the initiator. Depending on the size of the coils, ranges up to 10 cm and data rates of 106, 212, and 424 kBit/sec are possible.
Active Mode
When in active mode, both appliances generate an RF field. Each side transmits data by modifying its own field, using an Amplitude Shift Keying (ASK) modulation scheme. Advantages compared to passive mode is a larger operating distance (up to 20 cm) and higher transmission speeds (eventually over 1 MBit/sec). To avoid collisions only the sending device emits a electromagnetic field; the receiving entity switches off its field while listening. If necessary these roles can change as often as needed.
Usecases and Applications
An NFC compliant device offers the following modes of communication:
Reader/Writer Mode: In Reader/Writer mode an NFC system acts as an ordinary reader for contactless smart cards. If two or more cards are present in the reader’s carrier field one is selected using an anti-collision algorithm. NFC also takes care of sensing whether the chosen card is ISO 14443-A/B or FeLiCa compliant. The method used for anti-collision is dependent on the type of card detected. This mode causes the NFC device to act as an active device. From an application’s view there is no difference between a conventional and an emulated terminal, accesses to the contactless token proceed equally.
Operating in this mode, the NFC device can read and alter data stored in NFC compliant passive (without battery) transponders. Such tags can be found on e. g. SmartPoster allowing the user to retrieve additional information by reading the tag with an NFC device. Depending on the data stored on the tag, the NFC device takes an appropriate action without any user interaction. If e. g. an URI was found on the tag the handset would open a web browser.
Card Emulation Mode: Tag emulation mode is the reverse of reader/writer mode: A contactless token is emulated. Now the device acts soley in passive mode. Due to the fact that the card is only emulated it is possible to use one NFC wdevice to act on behalf of several „real“ smart cards. Which card is presented to the reader depends on the situation and can be influenced by software. Additionally an NFC device can contain a secure element to store the information for the emulated card in a secure way.
In this case an external reader cannot distinguish between a smart card and an NFC device in card emulation mode. This mode is useful for contactless payment and ticketing applications for example. Actually, an NFC enabled handset is capa-ble of storing different contactless smartcard applications in one device.
Peer-to-Peer Mode: This mode is specific to NFC. After having established a link between the two participants (the method is equal to ISO 14443-A) a transparent protocol for data exchange can be started. The data block size can be chosen freely, with an MTU (maximum transmission unit) limited to 256 bytes. Main purpose of this protocol is to enable the user to send his/her own data as soon as possible (i. e. after a few milliseconds). In a peer-to-peer session either both initiator and target can be in active mode or initiator in active and target in passive mode. This helps the target to reduce its energy consumption and is therefore especially useful if the initiator is a stationary terminal (e. g. a ticket counter) and the target a mobile device (e. g. a mobile phone).
The NFC peer-to-peer mode (ISO 18092) allows two NFC enabled devices to establish a bidirectional connection to exchange contacts, bluetooth pairing information or any other kind of data. Cumbersome pairing processes are a thing of the past thanks to NFC technology. To establish a connection a client (NFC peer-to-peer initiator) is searching for a host (NFC peer-to-peer target) to setup a connection. Then the Near Field Communcation Data Exchange Format (NDEF) is used to transmit the data.