... of industrial standard SIP protocol.Flexible configuration of one to four E1 / T1Guarantee 4E1 120 DS0 voice processing with ... G.723.1,G.729,GSM,iLBC,T.38)Ideal PSTN termination for IP phones, VoIP gateway, IPPBX, PBX accessEmbeded with RTP ... Channels), 2E1 (60 Channels), 4E1 (120 Channels)1T1 (24 Channels), 2T1 (48 Channels), 4T1 (96 Channels)· Voice ProcessingVoice Codec: G.711, G.729A, G.723.1, GSM ...