VOIP gateway

Support SIP(RFC3261, RFC3262, RFC3265) Support IAX2 Protocol Voice Codec: G.711A/u, G.729, G726, i LBC G.168 echo cancellation standard, compliant 96ms echo cancellation with speaker mode Adjust the volume: including the input and output of the handset and free- hand. Jitter Buffer, VAD, SIP, Domain name register, point-to-point Call SRV mode: can auto-swap between main and backup server RTP and RTCP Support the Inbound/Outbound transmission; SIP info, DTMF Relay, RFC2833 Many countries' standard ring NAT transversal: Support STUN, CITRON, AVS Mode Support SIP domain, SIP Authentication(none,basic,MD5), Domain Name parse Support two SIP server synchronously, including Pubic Server/ Private server, can make a call by either proxy Support redundancy public server,can auto swap to backup server when main server has problem. Support SIP application, including SIP Call forward/transfer/holding/waiting. Network Features Support two models: Bridge and Router, integrate two ports router function. Support basic NAT and NAPT. Support PPPoE for xDSL,and support off hook auto dial. Support DHCP Client for WAN. Support DHCP server for LAN. Support DNS relay for LAN, can provide DNS service for LAN Network equipment Use advanced DSP tech to insure high quality voice. Use advanced jitter buffer tech to prevent the delaying and losing for info package. Support Network Tools, including ping,race route,telnet client. Support three modes to configure WAN port IP, they are: static, DHCP, and PPPoE. Provide firewall control for small LAN. Provide optional priority level for small LAN. Support Secondly Layer QoS(802.1p) Advanced Functions It can register to two SIP server synchronously and a PSTN number, it has 2 VOIP number and 1 PSTN number, that means one phone has 3 numbers. Call waiting, call transfer, 3 parties' talking, many modes call forward. Switch outgoing call freely between VOIP and PSTN. Incoming display, forbid call out; setup avoid-disturb, auto answer, off hook auto dial, quick dial. Setup blacklist number and limit number. Support point-to-point call. Setup the end number method Setup fixed call method. Support Silence Suppression , VAD (Voice Activity Detection). Support CNG (Comfort Noise Generation). Support Echo Cancellation and AGC (Automatic Gain Control). Support Polarity reversal. Support VPN (L2TP), can be used in the VPN special network Support SIP register failure detection. Offer busy tone, when the telephone is out of order. Configuration, management and maintenance: Support safe mode and can update gateway via safe mode. Can configure the gateway by Web, Keyboard, Support to operate the gateway by keyboard, by Http mode to carry on management and configuration and support the filtration restriction on user IP address. Can update the software and configuration files via HTTP, FTP,TFTP. Support multi-administrator rights, user names ,passwords; Support reversal Telnet through NAT / Firewall to conduct long-distance management.