802.1aq Shortest Path Bridging (SPB) has been standardized by the IEEE as the next step in the evolution of the various spanning tree and registration protocols. 802.1aq allows for true shortest path forwarding in a mesh Ethernet network context utilizing multiple equal cost paths. This permits it to support much larger Layer 2 topologies@ with faster convergence@ and vastly improved use of the mesh topology. Combined with this is single point provisioning for logical connectivity membership@ which includes point-to-point@ point-to-multipoint@ and multipoint-to-multipoint variations. This memo documents the IS-IS changes required to support this IEEE protocol and provides some context and examples.