- Grandstream single line SIP telephone- 1 line appearance with FLASH to handle 2 simultaneous calls- HD wideband audio and full-duplex speakerphone with advanced acoustic echo cancellation- 128x32 graphical LCD with support for multiple languages- Broad interoperability with most of the leading IP PBX Softswitch platforms and 3rd party SIP devices and can be easily auto provisioned for mass deployment- Protocol/standards: SIP RFC3261 TCP/IP/UDP RTP/RTCP HTTP ARP/RARP ICMP DNS (A record and SRV) DHCP PPPoE TFTP NTP STUN SIMPLE- Feature keys: 3 dynamic context sensitive soft keys 3 navigation/menu/volume keys 7 dedicated function keys for: HOLD SPEAKERPHONE SEND TRANSFER CONFERENCE FLASH and HEADSET- Support for G.723.1 G.729 A/B G.711 u/a-law G.726 G.722 (wide-band) GSM and iLBC in- band and out-of-band DTMF (in audio RFC2833 SIP INFO) - Hold Mute Transfer Forward 3-way Conference Downloadable Phone Book (XML LDAP up to 200 items) Call Waiting Call Log Off-hook Auto Dial Auto Answer Click-To-Dial Downloadable Ringtones Server Redundancy and Fail-over Support - 2.5mm and RJ9 headset jack- Layer 2 (802.1Q 801.2p) and Layer 3 (ToS DiffServ MPLS) QoS- User and administrator level passwords MD5 and MD5- sess based authentication AES based secure configuration file SRTP - Firmware upgrade via TFTP/HTTP mass deployment using central secure provisioning file - Integrated (IEEE 802.3af) PoE- Universal power adaptor (Input: 100-240VAC 50-60Hz Output:+5VDC 1.2A UL Certified) includedGSGXP280