ITU refutes ISOC claims that split over MPLS OAM will harm the net

Stuart Corner
Thursday, 03 March 2011 12:46

Business IT - Technology

The International Telecommunication Union (IT) has hit back at claims from the Internet Society (ISOC) that its decision to split from the Internet Engineering Task Force (IETF) on MPLS standards will jeopardise the integrity of the Internet.

At a meeting on Friday 25t February 2011 in Geneva the ITU-T Study Group 15 determined a Recommendation that defines operations, administration and management (OAM) for MPLS transport networks that, according to ISOC, is at odds with an IETF standard, in spite of an agreement put in place by the ITU and the IETF two years ago to avoid such an outcome.

ISOC described this split as being without precedent and said: "the ITU has created a situation where, in the future there will be two groups of MPLS products that will not work together'¦Ongoing evolution along this path will jeopardise the globally interconnected Internet."

The ITU has responded by issuing a statement saying: "Experts'¦point to the fact that several interoperability tests have been successfully performed with no reported problems. In addition the solution being proposed by ITU conforms to the MPLS-TP architecture as defined by the IETF."

The ITU does not identify these 'experts' and acknowledges that interoperability may be compromised. "When network equipment uses different protocols, interoperability of the functioning of that protocol, in this case OAM, may well be affected."

However, it claims that the function of the Internet will not be affected. "Since packets for different protocols are identified by pre-assigned different codepoints, protocols running behind these different codepoints will not interfere with each other. This means that the core functionality - in this case Internet traffic - will not be affected. Therefore various protocols can coexist without causing any confusion in the network."

The ITU claims its decision to develop separate standards was taken only out of frustration with lack of progress in the IETF. "This solution was called for by a majority of the ITU membership in SG15 that has grown frustrated with a lack of progress in the development of a standard which is necessary to meet a market demand. Given that there are over 100,000 MPLS Transport Profile nodes already in transport networks, it is essential that the corresponding OAM toolset is standardised." The ITU has not identifed the make up of SG15, or the members who pushed this initiative.

According to the ITU: "in 2006 ITU started work on standards on T-MPLS, which leveraged a sub-set of MPLS that was targeted specifically for application in the transport network. However, in late 2007 the IETF indicated that T-MPLS may be in conflict with IP/MPLS. The ITU suspended work on T-MPLS and in 2008 agreed to work in cooperation with the IETF on the evolution of MPLS to meet the needs of the transport network. It was anticipated that the five existing Recommendations on T-MPLS would be replaced by mid 2009 with MPLS-TP Recommendations following within a year."

The ITU claims: "Some of the IETF input (RFCs) required to move forward were not made available and are currently still pending following the unilateral disbanding by the IETF of its group assigned to work with ITU in September 2009. ITU has issued a formal request for the necessary codepoints from IETF as these codepoints are currently administered by ICANN/IANA and can only be issued by IETF."