RequirementsforRingProtectioninMPLS-TP.ppt

Requirements for Ring Protectionin MPLS-TP John Drake (John.E.Drake2@) Adrian Farrel (adrian@olddog.co.uk) There is a base requirement draft-jenkins-mpls-mpls-tp-requirements-01 If protection is supported then MPLS-TP MAY support mechanisms that are optimized for specific network topologies (e.g. ring). These mechanisms MUST be interoperable with the mechanisms defined for arbitrary topology (mesh) networks. If optimised mechanisms for ring topologies are supported then they MUST support switching times within 50 ms (depending on CV rate configuration) assuming a reference network of a 16 node ring with less than 1200 Km of fiber, as defined by ITU SG15, Question 9. What do service providers say? “We want to deploy MPLS-TP in rings.” “We want to protect our traffic” That means we need to provide “ring protection” But what is a ring? Deployment Scenarios The network *is* the ring Deploy routers to replace TDM equipment Ring as a layer network The virtual rings imposed on a mesh network to provide connectivity Physical rings Physical topology is easy… An arrangement of two or more nodes each with exactly two line-side interfaces Layered Network A ring in the server layer can provide a set of TE links in the client layer The TE links are protected by the protection within the ring Virtual Rings We can super-impose a ring onto a mesh This creates a virtual or logical ring We can apply ring properties (whatever they are) to this ring Detailed Requirements Supplied by ITU based on draft version of G.8132 “T-MPLS Shared Protection Ring” Summarised and translated into English… A packet transport ring protection scheme shall: Be applicable at a packet transport layer, for both logical and physical ring topologies Operate in the data plane, i.e., be independent of a control plane or a management plane Have the capability to coordinate protection switching actions with resiliency mechanisms possibly operating at the server layer Support switching time within 50 ms Prot