The version is 3.3.0.0. TekSIP is a freeware SIP Registrar/Proxy. TekSIP complies with RFC 3261, RFC 3263, RFC 3311, RFC 3581 and RFC 3891. It supports NAT traversal, UPnP and ENUM. Please see technical details about NAT traversal in Readme.txt You can select IP address to be listened and...