Has anyone had experience with placing VoIP core services (CM, Unity, IPCC, etc) in a separate security zone from the rest of the campus through the use of the FWSM? We are about to migrate to that type of environment (where the campus is separated from the VoIP servers / gateways w/ use of FWSM) and wanted to hear some input. Has anyone run into any issues? Do you recommend a different solution to protect the VoIP core?

Thanks in advance