Protection for MPLS-TP multicast services

Abstract

This paper proposes three innovative point-to-multipoint protection schemes to provide efficient and reliable MPLS Transport Profile multicast services, which is particularly relevant for the fast growing IPTV broadcast service. The three proposed protection schemes are all based on the interconnected rings structure, which is a widely deployed topology of legacy networks and has the natural ability to support resiliency. The first protection scheme extends the protection methods defined in the latest IETF draft standard to the interconnected rings structure. The second protection scheme introduces an adapted OAM function, which has the ability to monitor the multicast service's status, such as configuration failures, software failures and performance degradation, to ensure the reliability of the whole branches and leaves of the multicast service. Furthermore, the interconnecting nodes of the rings make the protection switching decision, which releases the work to upgrade every node on the existing ring and thereby eases the MPLS Transport Profile network deployment. Instead of having one working path in one direction and the other direction being used as protection path, in the third protection scheme, the paths in both directions are used as working paths. When there is a failure, the two working paths protect each other, which increases the efficiency of the network resources. The traffic distribution on the ring is divided by these two separated working paths, which lowers the amount of affected entities when a failure occurs.