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Cisco uBR10012 Universal Broadband Router Software Configuration Guide
OL-1520-08
Chapter1 Overview of CiscouBR10012 Universal Broadband Router Software
Supported Software Features for the CiscouBR10012 Router
Restrictions
•The multicast definitions are per-bundle, not per interface. This means that all downstreams in a
bundle share the same multicast to QoS association. The downstreams will create their own service
flows according to the same QoS parameters.
•Multicast to QoS definitions can not be assigned per sub-interface
•Multicast SIDs are not deleted when a group becomes idle (no response to IGMP reports).
•The QoS assignments for a multicast group can not be changed dynamically. If the user wishes to
change them then a new “cable match” command must be configured.
•Multicast QoS is not supported on Multicast Echo on Cisco uBR10012 router.

New and Changed Commands

cable match address
Use the existing cable match command to assign QoS to a multicast group, with BPI either enabled or
disabled.
router# cable match address <number>|<name> [service-class <name> [bpi-enable]]
router# no cable match address [<number>|<name> [service-class <name> [bpi-enable]]]
debug cable mcast-qos
Use this command to turn on CMTS Multicast Qos debugging.
router# debug cable mcast-qos
SSM Mapping
Cisco IOS Release 12.3(17a)BC introduces Source-Specific Multicast (SSM) Mapping support on the
Cisco uBR10012 router.
When the SSM Mapping feature is configured, if a router receives an IGMP version 1 or version 2
membership report for a particular group G, the router translates this in one or more SSM (S, G) channel
memberships, such as IGMPv3 (S, G) INCLUDE membership reports) for the well known sources
associated with this group.
When the router receives an IGMP version 1 or version 2 membership report for group G, the router uses
SSM mapping to determine one or more source IP addresses (Si) for group G. SSM mapping then
translates the membership report as an IGMP version 3 report INCLUDE (G, [S1, G], [S2, G]...[Sn, G]
and continues as if it had received an IGMP version 3 report. The router then sends out PIM joins toward
(S1, G) to (Sn, G) and continues to be joined to these groups as long as it continues to receive the IGMP
version 1 or version 2 membership reports and as long as the SSM mapping for the group remains the
same.
When SSM Mapping feature is statically configured on the router, the source address or addresses (S)
can be discovered either by a statically configured table on the router or by consulting a DNS. When the
statically configured table is changed, or when the DNS mapping changes, the router will leave join to
the current sources associated with the joined groups.
For additional information about this feature, refer to the following documents on Cisco.com:
•Source Specific Multicast (SSM) Mapping
http://www.cisco.com/univercd/cc/td/doc/product/software/ios123/123newft/123t/123t_2/gtssmma.h
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