Again we see that the single CallBridge environment is considerably simpler than the clustered environment. One thing worth note above is that we have a contact domain specified. This is because if we do not specify the Fully Qualified Domain Name of our CallBridge as the local contact domain Lync/Skype will reject calls for security reasons. Since our incoming forwarding rules are set to use pass through, we will not actually be rewriting the from domain in this example.