Fast channel for quick spread of LSPs

The fast channel feature provides a quicker LSP propagation method than conventional LSP propagation. This feature spreads ISIS-SPB LSPs in the SPBM network by forwarding LSPs as data packets along the SPT in a dedicated SPB VSI. An SPBM node does not need to complete updating its LSDB before it propagates the topology change to the next node.

The I-SID for the fast-channel VSI is 255. To use the fast-channel feature, you must create a VSI and assign I-SID 255 to the VSI.

You cannot associate any Ethernet service instance with the VSI that uses I-SID 255 for data transmission.