4000 Router Series IP Multicast Configuration Guide

Figure 30 Relationship in view of geographical locations

As shown in Figure 30, for the multicast groups in a specific group address range, the

admin-scoped zones must be geographically separated and isolated. A router cannot belong to

multiple admin-scoped zones. An admin-scoped zone contains routers that are different from other

admin-scoped zones. However, the global-scoped zone includes all routers in the PIM-SM domain.

Multicast packets that do not belong to any admin-scoped zones are forwarded in the entire

PIM-SM domain.

• In view of multicast group address ranges:

Each admin-scoped zone is designated to specific multicast groups, of which the multicast group

addresses are valid only within the local zone. The multicast groups of different admin-scoped

zones might have intersections. All the multicast groups other than those of the admin-scoped

zones use the global-scoped zone.

Figure 31 Relationship in view of multicast group address ranges

As shown in Figure 31, the admin-scoped zones 1 and 2 have no intersection, but the

admin-scoped zone 3 is a subset of the admin-scoped zone 1. The global-scoped zone provides

services for all the multicast groups that are not covered by the admin-scoped zones 1 and 2,

G−G1−G2 in this case.

Admin-scope 3

G3 address

Admin-scope 2

G2 address

Admin-scope 1

G1 address

Global-scope

−G1−G2 address