... .723.1,G.729A/B,PCM A/U code Call forwarding, Call hold, Caller ID, DND standard voice service Anonymous call ... meet customer’s requirements:Supporting many applications such as call forwarding, caller ID, DND, busy tone, conference with IPPBX and Fax ... (32FXS) supports SIP 1.0/2.0.Main featuresSupport Call forwarding, Call waiting, Call display etc standard voice service and Busy ...