Grandstream GXP-2000 is a next generation enterprise IP telephone based on open industry standards. Built on innovative technologies, GXP-2000 features market leading superb audio quality, rich functionalities, and excellent manageability at affordable prices. Key Features: Multiline support of up to 11 lines indicators (expandable to a few dozen more through expansion key-module); 4 line indicators (expandable to 11), 7 programmable keys Graphical LCD to display up to 8 lines and 22 characters per line (multiple languages) Dual 10/100Mbps RJ45 Ethernet ports Call waiting, Hold, Mute, Transfer (blind or attended), Forward, and more Support Caller ID display or block (per call or permanent) Multi-party conferencing Voicemail indicator, call log, phone book, downloadable music ring tone Full duplex speaker phone with advanced echo cancellation, silence suppression Headset jack Integrated Power-over-Ethernet (802.3af and Cisco style) Support popular voice codecs including G.711, G.726, G.728, G.723, G.729, GSM, G7.22 (wideband) with dynamic negotiation of codec type and packet time Support SIP (RFC3261), TCP/IP/UDP, RTP/RTCP, HTTP, ARP, ICMP, DNS (A record and SRV), DHCP, PPPoE, TFTP, NTP Support NAT traversal (STUN... etc.), server fail-over, SIP Presence (SIMPLE), LDAP and SOAP (pending) Advanced jitter buffer control, packet delay and loss concealment technology Support remote device provisioning and firmware update via tftp and http Support syslog for device monitoring and 128-bit AES encryption of downloadable configuration information Support layer-2 (802.1Q VLAN and 802.1p) and layer-3 QoS (DiffServ, IP ToS)