EPCglobal Awards First Gen 2 Interoperability Certifications

Once an interrogator was put through these encoded chores, its ability to lock and unlock data using a password was also tested. "In addition to testing all the things Gen 2 tags and readers are supposed to do to interoperate with each other, we also made sure they couldn't do what they're not supposed to be able to do," says Morris. For example, the Gen 2 protocol says an interrogator should be able to lock, unlock or erase ("kill") data on a tag only by using a specific password for the tag. If an interrogator could successfully use an illegitimate password of all zeros to unlock a qualified tag, for instance, that tag would fail the test because no tag should be able to be unlocked with such a password. The same would be true if an interrogator were able to unlock a tag's data by means of an incorrect password.

The smaller set of test cases for printer-encoders focused on the device's ability to write data to the inlay of a label being printed.

In order to achieve an interoperability certification, a tag had to pass all the test cases with each interrogator and each printer-encoder. Conversely, an interrogator or printer-encoder had to pass all the test cases with each tag. When submitting a device to be tested for interoperability, the manufacturer provided the frequency range within the UHF band at which it wanted the device tested. For example, Paxar submitted three versions of its 9855 printer-encoder: one optimized for use in the United States, where devices function at 915 MHz, another optimized for use in E.U. nations at 866 MHz, and a third in Japan at 960 MHz.

Not all submitted devices passed all the test cases the first time they were tested, says Morris. Although all the devices conform to the Gen 2 standard, some manufacturers interpret the standard slightly differently, preventing one manufacturer's tags, for example, from interoperating with all other Gen 2 devices even though they might fully interoperate with a reader from that same manufacturer. Some products that initially did not pass the interoperability tests were modified and resubmitted, says Morris, but eventually, all 12 submitted products received the interoperability mark. All of the testing was held at MET's Baltimore test facility.

Going forward, Morris states, MET Labs will test individual products submitted for interoperability with the established pool of certified products on an on-demand basis. "We anticipate many more [Gen 2-certified] products will be tested and found compliant to interoperability specification in the next few weeks," he adds.