Gen 2 Faces Eight-Bit Obstacle

EPCglobal and the International Organization for Standardization clash over eight bits of data used to identify the Gen 2 tag numbering scheme.
Published: December 10, 2004

EPCglobal, the nonprofit organization charged with commercializing Electronic Product Code (EPC) technology, is on the verge of ratifying the long-awaited UHF Generation 2 specification, however that ratification may come with one issue still unresolved.

The issue is a dispute between EPCglobal and the International Organization for Standardization (ISO) over eight bits of data set to be used in Gen 2 to identify which numbering scheme a tag’s number relates too. For example, EPCglobal could decide to give the DOD its own eight-bit number to separate the DOD numbering system from all other EPC schemes.


Chris Diorio

While ISO would like all of those eight-bit numbers to follow its existing Application Family Identifier (AFI) scheme, EPCglobal wants to be sure it has enough eight-bit numbers to use for all its potential EPC numbering schemes and has suggested that it would adopt its own numbering system if its allotment of AFI numbers were too low. The key sticking point between the two groups, therefore, is the amount of AFI numbers the ISO plans to set aside for EPCglobal use.

“Within the ISO numbering system, EPCglobal will get at most 16 of the 256 values possible within that eight-bit number. EPCglobal says it needs its own numbering system and so we are arguing over these eight bits,” says Chris Diorio, cochair of the EPCglobal Hardware Action Group (HAG) and founder and chairman of Impinj, a Seattle-based manufacturer of passive RFID tags.

With no immediate resolution in sight, the EPCglobal HAG—which is charged with developing the Generation 2 specification—is asking its members to approve any outstanding changes to the Gen 2 specification except this AFI issue – with the promise of resolving the AFI issue separately “If the HAG approves [of passing the Gen 2 spec without the AFI resolved], then all the changes will get rolled into the Gen 2 spec except the AFI,” says Diorio.

Such a step would allow the board of governors at EPCglobal to ratify the Gen 2 specification before the end of year, while the AFI issue goes to a separate HAG sub-committee for resolution.

According to Diorio, it is not clear how the AFI issue will be settled, but EPCglobal is eager to have the issue resolved within the next six weeks, so that it could present the completed Gen 2 specification at next related ISO standards meeting, which is set for Jan. 21.

Last week, EPCglobal announced that demonstration testing on the proposed UHF Generation 2 specification had been completed and that the results validated the feasibility of the proposed standard (see EPCglobal Validates Gen 2 Spec).

EPCglobal has yet to release its findings regarding the validity of claims by Intermec Technologies that Intermec’s intellectual property is included in Gen 2 and that the company will be able to levy royalty payments from other companies producing Gen 2 compliant products. Diorio says, however, that IP issues are not a stumbling block for ratification of the standard.

“EPCglobal has made multiple statements, over a period of many months, that if after legal review any IP is found in the Gen 2 specification, then the specification would be sent back to committee for modification. That IP review has been going on for months, we are on the verge of ratification of the Gen 2 standard, and the HAG has had no requests to modify the spec on the basis of IP issues,” he says.

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