6. Resilience architectures

The aim of resilience architectures is to restore or protect the connection following a failure. A Pseudowire carried over an MPLS tunnel can rely on the resilience mechanisms of the underlying layer in the event of node or link failure within the IP/MPLS cloud. In fact, MPLS switching tables are updated in parallel with routing table updates caused by network failure. Mechanisms known as Fast ReRoute (FRR), linked to the use of RSVP-TE, provide local protection for each node and link in the MPLS tunnel. In the event of a failure, convergence times are of the order of 50 ms.