There has been a lot of buzz recently about a second OAM (Operations, Administration, and Maintenance) solution for MPLS-TP that will cause interoperability problems between MPLS-TP and MPLS. It is accurate that there is an alternative OAM based on ITU-T Y.1731 (Ethernet OAM) proposed by a number of vendors and countries and indeed, it will cause interoperability issues. As a strong believer in standards, I certainly hope that a second approach does not occur because vendors and customers do not need the additional cost burden that a lack of interoperability causes. The fact is that only the draft recommendation for MPLS-TP OAM based on Y.1731 has begun the first step in a very long approval ITU process – but nothing more – and in my estimates will take well over a year and could easily take up to two years to standardize. IETF MPLS OAM is widely deployed in MPLS networks today and will simply be extended as MPLS-TP is deployed as a next generation transport solution. In fact, recent interoperability testing of MPLS-TP took place at the MPLS World Congress earlier this month in Paris.
I believe that after careful consideration most operators will see the benefit of having a single end-to-end methodology to operate and manage converged packet optical transport networks, which MPLS-TP using MPLS OAM provides. Operators who select another method that is perceived to meet their short term needs now my ultimately learn that it fails to provide everything they had expected, and that having multiple OAM methods (one for Ethernet and another for MPLS) is not cost effective. It will be interesting to see what happens moving forward. At the very least, operators should make an informed decision on which approach is right for them.
- There is no second standard approved for MPLS-TP OAM.
- The market will ultimately decide which is the right approach based on which can provide the most economic benefit.
- IETF-based solutions are gaining momentum, and there have been two public interoperability events for IETF compliant MPLS-TP, one with Isocore and one with EANTC. Six vendors (Cisco Systems, Hitachi Ltd., NEC, Ixia, Metaswitch, and Ericsson) were included.
- Cisco believes that a single MPLS-TP OAM approach compliant to IETF protocols is the right one for the vast majority of operators who have an existing MPLS network and intend to migrate their transport networks to packet based solutions.