HPE 5820X Series, Руководство по настройке

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Figure 127 Building an SPT in IPv6 PIM-SSM
As shown in Figure 127 , Hosts B and C are IPv6 multicast information receivers. They send an
MLDv2 report message to the respective DRs to announce that they are interested in the information
about the specific IPv6 multicast source S and that sent to the IPv6 multicast group G.
The DR that has received the report first determines whether the IPv6 group address in this message
falls in the IPv6 SSM group range and then does the following:
•
If the IPv6 group address in the message falls into the IPv6 SSM group range, the IPv6
PIM-SSM model is built. The DR sends a channel subscription message hop by hop toward the
IPv6 multicast source S. An (S, G) entry is created on all routers on the path from the DR to the
source. An SPT is thereby built in the network, with the source S as its root and receivers as its
leaves. This SPT is the transmission channel in IPv6 PIM-SSM.
•
If the IPv6 group address in the message does not fall into the IPv6 SSM group range, the
receiver-side DR sends a (*, G) join message to the RP, and the source-side DR registers the
IPv6 multicast source.
NOTE:
In IPv6 PIM-SSM, the term "channel" refers to an IPv6 multicast group, and the term "channel
subscription" refers to a join message.
Relationship among IPv6 PIM protocols
In an IPv6 PIM network, IPv6 PIM-DM cannot work with IPv6 PIM-SM, IPv6 BIDIR-PIM, or IPv6
PIM-SSM. However, IPv6 PIM-SM, IPv6 BIDIR-PIM, and IPv6 PIM-SSM can work together. When
they work together, which one is chosen for a receiver trying to join a group depends, as shown
in
Figure 128 .
Source
Server
Host A
Host B
Host C
Receiver
Receiver
IPv6 multicast packets
SPT
Subscribe message
DR
DR
RP