TekSIP 2.9.0.0 is a Proxy Software product from teksip.com, get 5 Stars SoftSea Rating, TekSIP is a freeware SIP Registrar/Proxy. TekSIP complies with RFC 3261, RFC 3263, RFC 3311, RFC 3581 and RFC 3891. It supports NAT traversal, UPnP and ENUM. Please see technical details about NAT traversal in Readme.txt You can select IP address to be listened and alternative SIP endpoints for outgoing calls. You can also log session details into a log file and monitor active registrations and sessions in real-time. TekSIP can redirect calls to alternate endpoint when called endpoint is unavailable (Off-line, busy...).

TekSIP tested on Microsoft Windows XP and Windows 2003 server. Please see insallation requirements at Support section. and don't forget to read Readme.txt file comes with the distribution.

TekSIP also supports UPnP IGD specification. If installed behind UPnP supported Internet gateway device (ADSL router e.g.), TekSIP automatically detects if it is behind a new NAT gateway and the external IP address. All outgoing requests manipulated for NAT traversal. You do not need to add manual reverse mappings for SIP and RTP protocols.

TekSIP can optionally act as a B2BUA for incoming 3xx SIP responses. RADIUS Authentication (RFC 2865) and Accounting (RFC 2866) is supported.

TekSIP also provides single accounts proxy; if you have just one provider account and many internal clients, TekSIP proxies all external calls for the provider account.

TekSIP Features:
1. Supports features described in RFC 3261 and ENUM (e164.arpa domain only).
2. Logs system messages, errors and session information to a log file.
3. All parameters can be configured through management GUI.
4. Provides NAT traversal between registered SIP UAs.
5. You can define a default SIP route for outgoing calls.
6. You can redirect calls to alternate enpoint when called endpoint is off-line.
7. You can monitor active registrations and SIP calls in realtime.
8. Clears expired registrations automatically.
9. Stores configuration data in the installation directory (.ini file).
10. Quick and easy installation.

Limitations:
* This freeware version allows maximum 5 SIP endpoints registration and 5 simultaneous SIP sessions (Calls). SoftSea.com had fully tested, reviewed and uploaded the install files, TekSIP does not contain any adware or spyware, the latest version is 2.9.0.0, you can download this proxy software software (1.93 MB) from special server of SoftSea.com. The license of this networking software is Freeware, you can free download and free use this proxy software software.