To extend SPBM networks to other PBB networks, static MACs and ISIDs can be defined under SPBM SAPs/SDPs. The declaration of a static MAC in an SPBM context allows a non-SPBM PBB system to receive frames from an SPBM system. These static MACs are conditional on the SAP/SDP operational state. Currently this is only supported for SPBM because SPBM can advertise these B-MACs and ISIDs without any requirement for flushing. The B-MAC (and B-MAC to ISID) must remain consistent when advertised in the IS-IS database.
The declaration of static-isids allows an efficient connection of ISID based services. The ISID is advertised as supported on the local nodal B-MAC and the static B-MACs which are the true destinations for the ISIDs are also advertised. When the I-VPLS learn the remote B-MAC they associate the ISID with the true destination B-MAC. Therefore if redundancy is used the B-MACs and ISIDs that are advertised must be the same on any redundant interfaces.
If the interface is an MC-LAG interface the static MAC and ISIDs on the SAPs/SDPs using that interface are only active when the associated MC-LAG interface is active. If the interface is a spoke-SDP on an active/ standby pseudo wire (PW) the ISIDs and B-MACs are only active when the PW is active.