... interface for CDRAdvanced technologies including SIP protocol, Frequency domain echo cancellation and iLBC codec;Compatible with asterisk, ... NI-2, DMS, 5ESS· VoIP ProtocolSIP (RFC3261) , 2976 Info Method, 3515 Refer Method, 3581 Symmetric Response Routing· RADIUS ... RFC 2866 Accounting· DTMFDTMF Digits Transmit: RFC2833, INFO (SIP) , In-BandHardware· Ethernet Interface ConnectorRJ-45, ...