Cisco Cisco TelePresence Video Communication Server Expressway
Using a policy service to route calls
When using external policy servers to control call routing, the CPL returned to the VCS by the policy server
could change the destination alias of the call or add extra destinations. In these cases, the VCS will make
another request to the policy server for the new or modified destination aliases.
could change the destination alias of the call or add extra destinations. In these cases, the VCS will make
another request to the policy server for the new or modified destination aliases.
This may be a desirable feature in some scenarios, but often in order to save resources it will not be desirable
for the policy server to fully process calls it has already routed, especially in the case of routing and forking
where loops or excessive forking could occur.
for the policy server to fully process calls it has already routed, especially in the case of routing and forking
where loops or excessive forking could occur.
To assist in managing these scenarios, the “GLOBAL_CALL_SERIAL_NUMBER” can be used to identify
calls that the policy server has already processed. This value is unique per call, across all VCSs.
calls that the policy server has already processed. This value is unique per call, across all VCSs.
Round-robin routing to a member of a group
In this example an administrator wants to route calls to the member of a group who has least recently
received a call. This requires an alias which represents members of a group and a list of the members within
that group. The administrator still wants to retain the ability for users to call other users directly.
received a call. This requires an alias which represents members of a group and a list of the members within
that group. The administrator still wants to retain the ability for users to call other users directly.
Cisco TelePresence External Policy on Cisco VCS Deployment Guide (X8.5)
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Appendix 1: Design examples