Interface
ports: 24 fxs ports
telephony interfaces: rj11 and rj21 50-pin telco connectors
wan:1 10/100base-t ethernet
lan: 1 10/100base-t ethernet
indicators: ports status and activity leds
media processing
protocol: sip (rfc3261), iax2
transport: udp, tcp, tls, srtp
codec: g.711 (alaw/ulaw), g.722, g.723, g.726, g.729a/b, gsm, adpcm
voice capability: itu-t g.168 lec echo cancellation, dynamic jitter buffer, vad, cng, plc
dtmf mode: rfc2833, sip info, in-band
fax: t.38 and pass-through
qos diffserv, tos, 802.1 p/q vlan tagging