Distribution of Traffic Engineering Extended Admin Groups using BGP-LS

Administrative groups (commonly referred to as "colors" or "link colors") are link attributes that are advertised by link state protocols like IS-IS (Intermediate System to Intermediate System) and OSPF (Open Shortest Path First) and used for traffic engineering. These administrative groups have initially been defined as a fixed- length 32-bit bitmask. As networks grew and more use-cases were introduced, the 32-bit length was found to be constraining and hence extended administrative groups were introduced in the link state protocols. The 32-bit administrative groups are already advertised as link attributes in BGP-LS (Border Gateway Protocol Link-State). This document defines extensions to BGP-LS for advertisement of the extended administrative groups.