The requirements for MPLS Transport Profile include a requirement
(R93) that requires MPLS-TP must support recovery mechanisms for a
network constructed from interconnected rings that protect user data
that traverses more than one ring. In particular, This includes
protecting against cases of failure at the ring-interconnect nodes
and links. This document presents different scenario of
interconnected rings and special mechanism to address recovery of the
failure of ring-interconnect nodes and links. .
This document is a product of a joint Internet Engineering Task
Force(IETF) / International Telecommunications Union
Telecommunications Standardization Sector (ITU-T) effort to include
an MPLS Transport Profile within the IETF MPLS and PWE3 architectures
to support the capabilities and functionalities of a packet transport
network as defined by the ITU-T.