A Backward Recursive PCE-based Computation (BRPC) procedure to compute shortest inter-domain Traffic Engineering Label Switched Paths
Cisco Systems
The ability to compute constrained shortest Traffic Engineering (TE) Label Switched Paths (LSPs) in Multiprotocol Label Switching (MPLS) and Generalized MPLS (GMPLS) networks across multiple domains (where a domain is referred to as a collection of network elements within a common sphere of address management or path computational responsibility such as IGP areas and Autonomous Systems) has been identified as a key requirement. This document specifies a procedure relying on the use of multiple Path Computation Elements (PCEs) in order to compute such inter-domain shortest constraint paths along a determined sequence of domains, using a backward recursive path computation technique while preserving confidentiality across domains, which is sometimes required when domains are managed by different Service Providers.