Cisco TelePresence Administrator's Manual page 234

Bandwidth control
Bandwidth control examples
In this example, shown below, the endpoints in the Head Office register with the VCS Control, while those in
the Branch and Home offices register with the VCS Expressway. The introduction of the firewalls means that
there is no longer any direct connectivity between the Branch and Home offices. All traffic must be routed
through the VCS Expressway. This is shown by the absence of a link between the Home and Branch
subzones.
The VCS Expressway has subzones configured for the Home Office and Branch Office. These are linked to
the VCS Expressway's Traversal Subzone, with pipes placed on each link. All calls from the VCS
Expressway to the VCS Control must go through the Traversal Subzone and will consume bandwidth from
this subzone. Note also that calls from the Home Office to the Branch Office must also go through the
Traversal Subzone, and will also consume bandwidth from this subzone as well as the Home and Branch
subzones and Home Office, Branch Office and Head Office pipes.
This example assumes that there is no bottleneck on the link between the VCS Expressway and the Head
Office network, so a pipe has not been placed on this link. If you want to limit the amount of traffic flowing
through your firewall, you could provision a pipe on this link.
Because the VCS Control is only managing endpoints on the Head Office LAN, its configuration is simpler.
All of the endpoints in the Head Office are assigned to the Default Subzone. This is linked to the Traversal
Subzone, through which all calls leaving the Head Office must pass.
Cisco VCS Administrator Guide (X8.1.1) Page 234 of 507