HP A5500 SI Switch Series Configuration Manual page 353

IPv6 admin-scope zones correspond to IPv6 multicast groups with different scope values in their group
addresses. The boundary of the IPv6 admin-scope zone is formed by zone border routers (ZBRs). Each
IPv6 admin-scope zone maintains one BSR, which serves multicast groups within a specific scope. IPv6
multicast protocol packets, such as assert messages and bootstrap messages, for a specific group range
cannot cross the IPv6 admin-scope zone boundary. IPv6 multicast group ranges served by different IPv6
admin-scope zones can overlap. An IPv6 multicast group is valid only within its local IPv6 admin-scope
zone, functioning as a private group address.
The IPv6 global scope zone maintains a BSR, which serves the IPv6 multicast groups with the Scope field
in their group addresses being 14.
Relationship between IPv6 admin-scope zones and the IPv6 global scope zone
The IPv6 global scope zone and each IPv6 admin-scope zone have their own C-RPs and BSRs. These
devices are effective only in their respective IPv6 admin-scope zones. That is, BSR election and RP
election are implemented independently within each IPv6 admin-scope zone. Each IPv6 admin-scope
zone has its own boundary. The multicast information cannot cross this border in either direction. A
better understanding of the IPv6 global scope zone and IPv6 admin-scope zones should be based on
geographical space and group address range.
Geographical space
1.
IPv6 admin-scope zones are logical zones specific to particular multicast groups. The multicast packets
of these multicast groups are confined within the local IPv6 admin-scope zone and cannot cross the
boundary of the zone.
Figure 95 Relationship between admin-scope zones and the global scope zone in geographic space
As shown in
admin-scope zones must be geographically separated from one another. Namely, a router must not
serve different admin-scope zones. In other words, different admin-scope zones contain different routers,
whereas the global scope zone covers all routers in the IPv6 PIM-SM/IPv6 BIDIR-PIM domain. Multicast
packets that do not belong to any admin-scope zones can be transmitted in the entire IPv6 PIM-SM/IPv6
BIDIR-PIM domain.
Multicast group address Scope field
2.
As shown in
zone the corresponding multicast group belongs to.
Figure 95, for multicast groups with the same Scope field in their group addresses, IPv6
Figure 96, the Scope field in each IPv6 multicast group address indicates the admin-scope
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