This document builds on the GMPLS overlay model [RFC4208] and defines
extensions to the GMPLS User-Network Interface (UNI) to support route
diversity within the core network for sets of LSPs initiated by edge
nodes. A particular example where route diversity within the core
network is desired, are dual-homed edge nodes. The document also
defines GMPLS UNI extensions to deal with latency requirements for
edge node initiated LSPs.
This document is also applicable to the L1VPN framework [RFC4847] to
extend the L1VPN from the basic mode to the enhanced mode by
including additional constraints, focusing upon the overlay extension
service model. Route Diversity for customer LSPs are common
requirement applicable to L1VPNs. This document describes L1VPN
compatible mechanisms to achieve diversity for sets of customer LSPs.
The extended overlay service model can support other extensions for
L1VPN signaling, for example, those related to latency requirements.