If your company is required to comply with an RFID mandate set forth by the U.S. Department of Defense (DoD) or Wal-Mart, you must do so by following EPC (electronic product code) standards.
EPCglobal is the authority on how radio frequency identification (RFID) tags should be coded with information. The data content of RFID tags must be standardized for two key reasons: 1) so that all RFID readers are able to capture the tags’ data, and 2) so that your particular RFID implementation contains only unique tag identifiers.
There are several RFID interface protocols, each with varying capabilities, advantages, and disadvantages. Up until December 2004, EPCglobal’s First Generation Classification (Gen-1) system was the most widely used standard. The second-generation system (Gen-2) is favored after December 2004 and is the standard to follow when satisfying the requirements of the DoD and Wal-Mart RFID mandates.
RFID tags are classified as Class 0 through Class 5, depending on their functionality:
Class 0 – UHF; read-only, preprogrammed passive tags, meaning that end users cannot write a new number to the tag
Class 1 – UHF or HF; write once, read many (WORM)
Class 2 – Passive read-write tags that can be written to at any point in the supply chain
Class 3 – Read-write with onboard sensors capable of recording parameters like temperature, pressure, and motion; can be either semipassive or active
Class 4 – Read-write active tags with integrated transmitters; can communicate with other tags and readers
Class 5 – Similar to Class 4 tags but with additional functionality; can provide power to other tags and communicate with devices other than readers
A designation of “Generation 1.0” and “Generation 2.0” associated with a class (e.g., Class 1 Generation 2.0) is more indicative of the tag’s functionality than the class name itself, as Gen-2 tags represent standardized improvements over their Gen-1 predecessors.
Generation 2 of the EPC protocol offers several advantages, including but not limited to:
– An interoperable, global standard
– Faster and more flexible read speeds
– Faster, more accurate performance through the use of advanced anticollision protocols
– An easier way to deploy many readers at one time to end users
– Enhanced security and privacy
Additionally, Class 1 Gen-2 RFID tags are backward-compatible with Gen-1 Class 0 and Class 1 tags and replace the specifications for both classes. Generation 2.0 Class 1 tags have an open standard that any manufacturer can use to produce their tags.