H3C Technologies H3C S7500E Series Switches - Manual (Page 329)

12-9
z If G is not in the IPv6 SSM group range, Router A cannot provide the SSM service but the ASM
service.
z If G is in the IPv6 SSM group range but no MLD SSM mappings corresponding to the IPv6
multicast group G have been configured on Router A, Router A cannot provide SSM service and
drops the packet.
z If G is in the IPv6 SSM group range, and the MLD SSM mappings have been configured on
Router A for multicast group G, Router A translates the (*, G) information in the MLD report into
(G, INCLUDE, (S1, S2...)) information based on the configured MLD SSM mappings and provides
SSM service accordingly.
The MLD SSM mapping feature does not process MLDv2 reports.
For more information about the IPv6 SSM group range, refer to IPv6 PIM Configuration in the IP
Multicast Configuration Guide.
MLD Proxying
In some simple tree-shaped topologies, it is not necessary to configure complex IPv6 multicast routing
protocols, such as IPv6 PIM, on the boundary devices. Instead, you can configure MLD proxying on
these devices. With MLD proxying configured, the device serves as a proxy for the downstream hosts
to send MLD messages, maintain group memberships, and implement IPv6 multicast forwarding
based on the memberships. In this case, each MLD proxy device is a host but no longer an IPv6 PIM
neighbor to the upstream device.
Figure 12-6 Network diagram for MLD proxying
As shown in Figure 5-4 , two types of interfaces are defined on a MLD proxy device: