| 摘要 |
Router elements R1, R2 of a packet network 100 using a sparse mode multicast protocol are configured as candidate rendezvous points (RPs). The candidate RPs use a virtual IP address. In each shared subnet, there is selected from among the candidate RPs a single designated candidate rendezvous point (DCRP) and zero or more virtual candidate rendezvous points (VCRPs). The DCRP serves as an active candidate RP (and when elected, performs RP functions); and the VCRP(s) serve as backup to the DCRP. The VCRP(s) maintain state information to facilitate rapid takeover of DCRP functionality upon failure of the DCRP. In one embodiment, geographically separate domains 1006, 1008 are each implemented with separate active DCRPs, defining multiple, simultaneously active anycast RPs (DCRP1, DCRP2) with MSDP peering between the DCRPs. The DCRP(s) may include backup VCRP(s) for redundancy. |
