TP21s

4 SIP account Call hold, mute, DND One-touch speed dial, hotline Call forward, call waiting, call transfer Redial, call return, auto answer, direct IP call 5-way conferencing Group listening, SMS, emergency call Ring tone selection/provisioning Set date time automatically or manually Dial plan per account RTCP-XR (RFC3611), VQ-RTCPXR (RFC6035) Action URL/URI