HPE 5820X Series, Configuration Manual

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If G is not in the IPv6 SSM group range, Router A cannot provide the SSM service but can
provide the ASM service.
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If G is in the IPv6 SSM group range but no MLD SSM mappings have been configured for the
IPv6 multicast group G on Router A, Router A cannot provide SSM service and drops the
packet.
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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.
NOTE:
The MLD SSM mapping feature does not process MLDv2 reports.
For more information about the IPv6 SSM group range, see " Configuring IPv6 PIM ."
MLD proxying
In some simple tree-shaped topologies, you do not need 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, the MLD proxy device is a host but no longer an
IPv6 PIM neighbor to the upstream device.
Figure 112 Network diagram
As shown in Figure 112 , an MLD proxy device has the following types of interfaces:
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Upstream interface
—Also called the "proxy interface." A proxy interface is an interface on
which MLD proxying is configured. It is in the direction toward the root of the multicast
forwarding tree. An upstream interface acts as a host that is running MLD, and it is also called a
"host interface."
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Downstream interface
—An interface that is running MLD and not in the direction toward the
root of the multicast forwarding tree. A downstream interface acts as a router that is running
MLD and it is also called a "router interface."
A device with MLD proxying configured maintains a group membership database, which stores the
group memberships on all downstream interfaces in this database. Each entry comprises the