... 2000(32FXS) is fully compatible with SIP industry standard, can be achieved with many other SIP compliant ... IP and PSTN.Large port access gateway Standard SIP protocols Standard G.723.1,G.729A/B, ... Call waiting, Call display etc standard voice service and Busy tone, Fax over IP, Three-way conference . ... input:100-240VAC/50HzEnvironmentalOperational:32-104°For 0-40°CStorage:14-140°For -10-60°CHumidity:10 ...