Key Features:

SIP 2.0 (RFC3261) IAX2 protocol (optional) Supports PSTN (Optional) The possibility of recording 4 SIP accounts, also as a backup The ability to simultaneously login to all servers Voice Codecs: G.711a / u, G.7231 high / low, G.729a / b, G.722, G.726, iLBC, AMR-NB; AMR-WB Video codecs: H.263, H.264, MPEG4 Video resolution: QCIF, CIF, QVGA Photo Format: PEG GIF and BMP PNG Video formats: MP4, 3GP and FLV Echo cancellation: G.168 compatible with the LEC, including hands-free (AEC) VGS, VAD, CNG, jitter buffer Speakerphone full-duplex Possibility of registering a domain or implementation of SIP calls peer to peer Modes DTMF inband, SIP info, RFC2833 Can be used for custom ring tones Support for STUN Support for the SIP SMS Adjusting the volume in all modes (headPhone / handsfree / headPhone wire / bell) HD voice with high quality headPhone / HD voice in speakerphone mode