H3C Technologies H3C S12500-X Series Switches - Manual (Page 165)

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Table 10 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 ."
DR election
IPv6 PIM-SSM uses the same DR election mechanism as IPv6 PIM-SM. For more information, see " DR
election ."
SPT building
The decision to build an RPT for IPv6 PIM-SM or an SPT for IPv6 PIM-SSM depends on whether the IPv6
multicast group that the receiver wants to join is included in the IPv6 SSM group range (FF3x::/32
reserved by IANA, where "x" represents any legal address scope).