Hello freinds, I have a question here, hoping someone can give me a help. A Cisco IP Phone is registering in the CUCM successfully, if it is in the office where deploys firewall controll, the phone can't communicate with other phones out of its network environment. One way is open ACL in firewall, another way is using the CUCM as relay, When we set the "Use Trusted Relay Point" to ON, how will it impact on CUCM, does the system load can be quantized ?