4000 Router Series IP Multicast Configuration Guide

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Figure 50 IPv6 multicast address format

An IPv6 admin-scoped zone with a larger scope field value contains an IPv6 admin-scoped zone

with a smaller scope field value. The zone with the scope field value of E is the IPv6 global-scoped

zone. Table 6 lists the po

ssible values of the scope field.

Table 6 Values of the Scope field

Value Meaning Remarks

0, F Reserved N/A

1 Interface-local scope N/A

2 Link-local scope N/A

3 Subnet-local scope IPv6 admin-scoped zone.

4 Admin-local scope IPv6 admin-scoped zone.

5 Site-local scope IPv6 admin-scoped zone.

6, 7, 9 through D Unassigned IPv6 admin-scoped zone.

8 Organization-local scope IPv6 admin-scoped zone.

E Global scope IPv6 global-scoped zone.

IPv6 PIM-SSM overview

The ASM model includes IPv6 PIM-DM and IPv6 PIM-SM. The SSM model can be implemented by

leveraging part of the IPv6 PIM-SM technique. It is also called "IPv6 PIM-SSM."

The SSM model provides a solution for source-specific multicast. It maintains the relationship between

hosts and routers through MLDv2.

In actual applications, part of MLDv2 and IPv6 PIM-SM techniques are adopted to implement the SSM

model. In the SSM model, because receivers have located an IPv6 multicast source, no RP or RPT is

required, and no source registration process is required for discovering IPv6 multicast sources in other

IPv6 PIM domains.

The operating mechanism of IPv6 PIM-SSM is summarized as follows:

• Neighbor discovery

• DR election

• SPT building

Neighbor discovery

IPv6 PIM-SSM uses the same neighbor discovery mechanism as IPv6 PIM-SM. For more information, see

"Neighbor discovery."