H3C Technologies H3C S7500E Series Switches - Manual (Page 150)

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Figure 6-7 Relationship between admin-scope zones and the global scope zone in geographic
space
As shown in Figure 6-7 , for multicast groups in the same address range, 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 PIM-SM domain. Multicast packets that
do not belong to any admin-scope zones can be transmitted in the entire PIM-SM domain.
2) In terms of multicast group address ranges
Each admin-scope zone serves specific multicast groups. Usually, these addresses have no
intersections; however, they may overlap one another.
Figure 6-8 Relationship between admin-scope zones and the global scope zone in group
address ranges
In Figure 6-8 , the group address ranges of admin-scope 1 and 2 have no intersection, whereas
the group address range of admin-scope 3 is a subset of the address range of admin-scope 1.
The group address range of the global scope zone covers all the group addresses other than
those of all the admin-scope zones. That is, the group address range of the global scope zone
is G-G1-G2. In other words, there is a supplementary relationship between the global scope
zone and all the admin-scope zones in terms of group address ranges.