The only required
IPv6 configuration on a cable line card interface is the IP provisioning mode.
The remainder of the IPv6 features are configured at the virtual bundle
interface, which is then associated with a particular cable line card interface
to establish its configuration.
Most of the IPv6
features that are supported in interface configuration mode (both
cable-specific as well as platform-independent IPv6 features) are configured at
a cable bundle interface.
The Cisco CMTS
routers support IPv6 routing on the bundle interface and map both IPv6 unicast
and multicast addresses into the cable bundle forwarding table, for packet
forwarding.
Each bundle
interface has a unique link-local address (LLA) to support link-local traffic
when IPv6 is enabled. Cisco CMTS routers can support a maximum of 40 active
bundle interfaces, which also translates to a maximum of 40 active IPv6-enabled
bundle interfaces.
IPv6 commands can be configured on multiple bundle
subinterfaces.