Single port with PSTN VoIP gateway supporting SIP/IAX2 protocol, support VPN, auto provisioning, VLAN. Via enterprise VPN and IP private line,it supports simultaneous access of IP audio and date service.Besides,it is gateway with PSTN suitable for VOIP service provider, can work with Asterisk IP PBX perfectly.

Support Protocol:

Support SIP (RFC3261, RFC2543)
Support IAX2
Support Reverse polarity
Support voice code: G711A/u, G729, G726, iLBC
Support G.168 echo cancellation standard, compliant 96ms echo cancellation with speaker
Support Jitter Buffer, VAD, CNG, SIP/IAX2, domain name register, point to point communication.
Support the voice communication through RTP and RTCP.
Support the DTMF Inbound/Outbound transmission; SIP info, DTMF Relay, RFC2833
Support standards of the ring in different countries and regions.
NAT penetration, support STUN client, CITRON, AVS etc..
Support SIP domain, SIP Authentication (none basic, MD5), domain name parse.
Support two SIP servers (Public Server / Private Server) synchronously, make a call by either proxy.
Support SIP application, including SIP Call forward/transfer/holding/waiting.
Support L2TP protocol

Network Features:

Support two models: Bridge and Router, and integrates the router functions of these two ports.
Support basic NAT and NAPT
Support PPPoE for xDSL, and support redial automatically when its offline
Support DHCP client for WAN port
Support DHCP server for LAN port
Support DNS relay for LAN port, and provide DNS service for LAN network devices.
Use the advanced technology DSP to ensure high quality voice
Use the advanced buffer technology to avoid the information package delay too long or lost.
Support Network Tools that includes ping, trace route and telnet client
Support 3 methods to configure the WAN IP: Static (static configuration for LAN), DHCP (Dynamic query through LAN) and PPPoE (Dynamic query through ADSL) 
Provide firewall control for small size of LAN port
Provide the communication PRI available for the small LAN of LAN port
Support Qos (802.1p) for the second Layer

Advanced Functions:

It can register to two SIP server synchronously,one IAX2 systems and a PSTN number, it has 3 VOIP number and 1 PSTN number, that means one phone has 4 numbers
Call waiting, call transfer, 3 ways calling, 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
Support line detection, busy tone when no line available

Configuration, management and maintenance:

Support post mode and can update gateway via post mode
Support to operate and configure the gateway by keyboard and Http mode, and support the filtration restriction on user IP address
Support to update the software and configuration via HTTP, FTP, TFTP
Support multi-administrator management, user name, password; Support reversal Telnet through NAT/ Firewall to manage long-distance.

Model Main Feature	IAD308	IAD1010	IAD100T (PSTN)	IAD2020
Ethernet port	1 WAN	1WAN 1LAN	1WAN 1LAN	1WAN 1LAN
FXS	1	1	1	2
FXO		1
SIP	√	√	√	√
IAX2			√
VPN			√	√
PPPOE	√	√	√	√
Registration	1SIP	2line(FXO+FXS)	2SIP,1IAX2,1lifeline	2 line(2FXS)
G711/T.38	√	√	√	√
Voice Code	G.711A/u, G.723,G726, ILBC,729 A/B	G.711A/u, G.723high/low, G.726, iLBC, G.729 A/B	G.711A/u,G.726, iLBC, G.729 A/B	G.711A/u,G.723, iLBC, G.729
Route/Bridge		√	√	√
Caller ID Display	√	√	√	√
3 way call	√	√	√	√
Call Forward	√	√	√	√
Blind/attend transfer	√	√	√	√
Certification	CE/FCC	CE/FCC/RoHS	CE/FCC/RoHS	CE/FCC/RoHS

Our IAD serial gateway supports SIP protocol to enable users to make local, long distance and international telephone/FAX calls by using existing telephony device.