The NFC Forum revealed its technology architecture and announced the first five Forum specifications for near-field communications (NFC) last week. When complete, the NFC Forum’s technology architecture will include specifications that define a modular NFC device architecture, as well as protocols for interoperable data exchange and device-independent service delivery, device discovery, and device capability (see figure).
Initial specifications include an NFC data-exchange format (NDEF) specification that specifies a common data format for devices and tags. Also, an NFC record-type definition (RTD) specification specifies standard record types used in messages between devices and between devices and tags. Full specifications will be revealed in the third quarter.
The RTD specs include a “Smart Poster” specification (for records containing plain text that can be read by NFC-enabled devices), text RTD specification (for records containing plain text), and a uniform resource identifier (URI) specification (for elements that refer to an Internet source that can be read by NFC-enabled devices).
In addition to unveiling the NFC Forum architecture and initial specifications, the Forum announced the initial set of tag formats that all NFC Forum-compliant devices must support. Tags are ICs that store data that can be read by NFC-enabled devices. The Forum’s selected tags are based on the International Organization for Standardization (ISO) 14443 Type A and B standards and Sony’s FeliCa.
ISO 14443 is a four-part international standard for contactless smart cards operating at 13.56 MHz in close proximity with a reader antenna. FeliCa is derived from ISO 18092, passive communication mode. Tags compatible with the Forum’s mandatory formats are available initially from Innovision, Philips, Sony, and other vendors. More than a billion NFC-ready tags already are deployed globally.
The NFC Forum selected the initial tags to accommodate a broad range of applications and device capabilities. NFC Forum Tag Types 1 and 2, based on ISO 14443 A, have small memory capacity (1 and 2 kbytes) and thus a low cost. They operate at relatively low speed (106 kbits/s) and are driven by specific command sets.
NFC Forum Tag Type 3 is based on FeliCa. It’s a more flexible, moderate-cost tag with significantly larger memory (up to 1 Mbyte) and higher speed (212 kbits/s). Tag Type 4, also flexible and moderate in cost, is based on ISO 14443, with memory up to 64 kbytes and speed of 106 to 424 kbits/s.