Adding a SIP PBX
ICE Server provides private call connections between ICE users on ICE Desktop or Mobile, but does not provide a PTSN connection. For that you must deploy a SIP PBX. This section describes how to add a PBX as a registrar or as a SIP Trunk for call routing and outside calling. For instructions on configuring a Telephony Gateway see ICE Gateway.
Note: A PBX is not required for Private Calls between ICE users. It is only required to connect calls with the Public Switched Telephone Network (PSTN).
Once a PBX has been added, any appropriately configured Instant Connect client will function as a "soft phone," extending voice communication to the public telephone network. Not only does this allow ICE clients to make external telephone calls, but external telephone callers can dial directly into an ICE channel that's been configured to accept outside callers. The telephone caller can speak on the channel by pressing the * key to request the floor, and the # to relinquish it.