HP VSR1000 Configuration Manual page 148

Default-MDT establishment in a BIDIR-PIM network
Figure 54 Default-MDT establishment in a BIDIR-PIM network
As shown in
A. The process of establishing a default-MDT is as follows:
PE 1 initiates a join to the public network RP by specifying the multicast group address as the
1.
default-group address in the join message. A (*, 239.1.1.1) state entry is created on each
device along the path on the public network.
At the same time, PE 2 and PE 3 separately initiate a similar join process. Finally, a
receiver-side RPT is established in the MD, with the public network RP as the root and PE 1, PE
2, and PE 3 as leaves.
PE 1 sends a multicast packet with the default-group address as the multicast group address.
2.
The DF of each network segment on the public network forwards the multicast packet to the RP.
Each device on the path creates a (*, 239.1.1.1) state entry.
At the same time, PE 2 and PE 3 separately initiate a similar process. Finally, three source-side
RPTs are established in the MD, with PE 1, PE 2, and PE 3 as the roots and as the public
network RP as the leave.
The receiver-side RPT and the three source-side RPTs constitute the default-MDT in the
3.
BIDIR-PIM network.
Figure 54, BIDIR-PIM runs on the network, and all the PE devices support VPN instance
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