3 Programmable keys that come pre-programmed and labelled with default values: Callers, Redial and Transfer, 4-way navigation with Select/OK key, Aastra Hi-Q Audio Technology, Audio and Codecs:, Backup proxy/registrar server support, Codecs:, Comfort noise utilization, CTI applications, Dedicated function keys including: Transfer, Callers List, Hold, Redial, Goodbye, Options, 2 volume keys, Mute (with LED) and Speaker (with LED), Display control based on user actions or events, DNS-SRV, Dual 10/100 Mbps Ethernet ports with hardware based Ethernet switch, Dynamic Phone Configuration, Echo cancellation, Extensive XML documentation and sample Apps, Full-duplex quality speakerphone, G.711, G.729, G.722, AMR, AMR-WB(G.722.2), G.726, iپوندC, BV16, BV32, L16, Headset Mode support, Hearing Aid Compatible: Yes, IEEE 802.1x, Integrated HTTP/HTTPS server for web administration and maintenance including a built-in troubleshooting section, LLDP-MED, Manual or Dynamic Host Configuration Protocol (DHCP) IP address setup, Mass deployment via central provisioning of user configuration files – TFTP, FTP, HTTP, HTTPS, Network Address Translation (NAT), STUN, TURN support, Networking and Provisioning:, Packet loss concealment, Quality of Service support – IEEE 802.1 p/Q VLAN and priority tagging, Type of Service (TOS), and Differentiated Services Code Point, Redundant server support, RTP Streaming Control, RTP streaming for Paging and Intercom applications, SNTP, Support of multiple DHCP options: 2,12,42,43,60,66,77,120,132,159,160, Time and date synchronization using, TR-069 support, Up to 2 lines on dedicated line keys with LED, Voice Quality Metrics, including MOS, Wideband handset and speakerphone, XML API Capabilities: