Replicating Multicast Packets

The Juniper Networks T-series routers handle extreme multicast packet replication requirements with a minimum of router load. Each memory component only needs to replicate a multicast packet at most twice. Even in the worst-case scenario involving maximum fan-out, with one input port and 63 output ports needing a copy of the packet, the T-series router only copies a multicast packet only six times. Most multicast distribution trees are much sparser, so in many cases only two or three replications are necessary. In no case does the T-series architecture have an impact on multicast performance, even with the largest multicast fan-out requirements.