A system and method are provided that enable a registrar or other server or proxy device to be used to provide a path between a pair of endpoint devices for exchanging addressing information, in order to establish a direct P2P connection. Once that connection is established, the connection may be used for any P2P data communications, e.g. SIP establishment of a VoIP call, instant messaging, online gaming, file transfer, multimedia streaming, etc. In this way, each endpoint device possesses a list of candidate addresses to establish a direct P2P connection, which may then be used for any type of communication. By relying on a registrar or other server to enable the candidate lists to be exchanged, control can still be maintained if necessary, since the candidate lists can be modified, e.g. to enable a transparent interception, to impose or remove security restrictions, etc.