At network ingress, broadcast, multicast, and unknown (BMU) traffic identified using DSCP and/or EXP (also known as LSP TC) is mapped to a forwarding class (FC). Since BMU traffic is considered to be multipoint traffic, the queue hosting BMU traffic must be configured with the multipoint keyword. Queues 9 through 16 support multipoint traffic (see Table: Default Network Ingress QoS Policy). For any adapter card hosting any number of network ports, up to 16 queues can be configured to host 8 unicast and 8 multicast queues.
Similar to unicast queues, BMU queues require configuration of:
queue depth (committed and maximum)
scheduled rate (committed and peak)
In addition, as is the case for unicast queues, all other queue-based congestion management techniques apply to multipoint queues.
The benefits of using multipoint queues occur when the to-fabric shapers begin scheduling traffic towards the destination line card. To-fabric shapers can be configured for aggregate or per-destination mode. For more information, see BMU Support.