Analysts' hunch is that the fracas over MPLS-TP may cause the standard to split in two, just as Sonet and SDH did.

"I do think they have gotten to a point where we may end up like Sonet and SDH, where each country area settles on one type, and vendors will have to support both types," says Eve Griliches, an analyst with ACG Research .

The Internet Engineering Task Force (IETF) and International Telecommunication Union (ITU) are working jointly on an MPLS-TP standard. But given the rancor at the standards meetings earlier this month, it doesn't look like the argument over operations, administration, and maintenance (OAM) will get settled easily. (See Rumor: T-MPLS Group Gets Shouted Down and MPLS-TP Delays Keep T-MPLS Alive.)

The IETF meeting briefly became a shouting match as supporters of Y.1731 -- an ITU standard created as part of the old T-MPLS concept -- demanded a chance to present what's called the BHH draft, which describes the use of Y.1731 for OAM in MPLS-TP.

Many at the IETF had considered the Y.1731 matter to be closed. The working group had instead favored the BFD approach, partly because of its interoperability with Multiprotocol Label Switching (MPLS). But China Mobile Communications Corp. has deployed Y.1731 already, and Telecom Italia (TIM) seems prepared to do the same.

It's the weight of those names -- along with Alcatel-Lucent (NYSE: ALU) and Huawei Technologies Co. Ltd. , whose representatives are the BHH draft's principal authors -- that make it unlikely Y.1731 will just go away, says Heavy Reading analyst Sterling Perrin.

"To me, the best outcome would be just to have two variants," Perrin says. "The group leadership just seems dead set against it. They could just all move to one standard, but that seems unlikely" and would probably result in the Y.1731 camp continuing to implement their technology even without the backing of the standard.

Separately, carriers are putting pressure on vendors to settle on a standard, so that officially standards-based equipment can be fruitful and get deployed.

"The feeling I got from Berlin [site of November's ITU meeting] is that the vendors are going to have to settle things," Griliches says.

— Craig Matsumoto, West Coast Editor, Light Reading