1. Support H.323 V4,SIP v2.0 (RFC 3261),MGCP (RFC 3435) 2. Codec: G. 711,G.723.1,G.726 and G.729A/B 3. Built-in Router function 4. Hybrid echo cancellation G.168 (16 ms) 5. Auto switch between Fax and voice 6. DTMF tone detection/regeneration 7. Comfort Noise Generation (CNG) 8. User programmable Call Progress detection/generation 9. Voice Activity Detection (VAD) Facsimile protocol (option): T.38 10. Real-time fax over IP 11. DTMF tone detection/regeneration HTTP Server TFTP and flash memory for remote software download and upgrade