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cannot cross the IPv6 admin-scoped zone boundary. IPv6 multicast group ranges served by different IPv6
admin-scoped zones can overlap. An IPv6 multicast group is valid only within its local IPv6
admin-scoped zone, functioning as a private group address.
The IPv6 global-scoped zone maintains a BSR, which serves the IPv6 multicast groups with the Scope
field in their group addresses being 14.
Relationship between IPv6 admin-scoped zones and the IPv6 global-scoped zone
The IPv6 global-scoped zone and each IPv6 admin-scoped zone have their own C-RPs and BSRs. These
devices are effective only on their respective zones, and the BSR election and the RP election are
implemented independently. Each IPv6 admin-scoped zone has its own boundary. The IPv6 multicast
information within a zone cannot cross this boundary in either direction. You can have a better
understanding of the IPv6 global-scoped zone and IPv6 admin-scoped zones based on geographical
locations and the scope field values.
•
In view of geographical locations
An IPv6 admin-scoped zone is a logical zone for particular IPv6 multicast groups with the same
scope field value. The IPv6 multicast packets for such IPv6 multicast groups are confined within the
local IPv6 admin-scoped zone and cannot cross the boundary of the zone.
Figure 91
Relationship in view of geographical locations
As shown in
, for the IPv6 multicast groups with the same scope field value, the IPv6
admin-scoped zones must be geographically separated and isolated. The IPv6 global-scoped
zone includes all routers in the IPv6 PIM-SM domain or IPv6 BIDIR-PIM domain. IPv6 multicast
packets that do not belong to any IPv6 admin-scoped zones are forwarded in the entire IPv6
PIM-SM domain or IPv6 BIDIR-PIM domain.
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In view of the scope field values
In terms of the scope field values, the scope field in an IPv6 multicast group address shows which
zone the IPv6 multicast group belongs to.