... .723.1,G.729,GSM,iLBC,T.38)Ideal PSTN termination for IP phones, VoIP gateway, IPPBX, PBX accessEmbeded with RTP voice proxy ... )· Voice ProcessingVoice Codec: G.711, G.729A, G.723.1, GSM, iLBCEcho Cancellation: G.168, tail length: 8/16/32/64 ... with DTMFRingback Tone· Voice Proxy RTP Voice Proxy Function (for NAT/Firewall Traversal)· Fax ProcessingT.30, T.38 Fax Relay· BillingRadius Interface· Gateway ...