3com S7906E Installationsanweisungen

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Figure 1-7 Relationship between admin-scope zones and the global scope zone in geographic space 

 

 

 

As shown in 

, 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 1-8 Relationship between admin-scope zones and the global scope zone in group address 

ranges 

 

 

In 

, 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.