Multi-Topology/Multi-Instance ISIS for IPv4-Embedded IPv6
France Telecom
France Telecom
Huawei
Comcast
This document defines two new Multi Topology Routing Identifiers (MT IDs), based on [RFC5120] and two new Instance Identifiers (MI IDs), based on [I-D.ietf-isis-mi], respectively, in the Intermediate System to Intermediate System. With these identifiers, an IPv4-Embedded IPv6 topology is maintained for both IPv6 unicast and multicast traffic. The purpose of running separate instances or topologies for IPv4-Embedded IPv6 traffic is to distinguish from the native IPv6 routing topology, and the topology that is used for routing IPv4- Embedded IPv6 datagrams only. Separate instances/topologies are also meant to prevent any overload of the native IPv6 routing tables by IPv4-Embedded IPv6 routes.