TekPhone is a SIP (Session Initiation Protocol) VoIP Softphone that provides UA agent functions (Based on RFC 3261) runs under Windows (XP, Vista, 2003 Server). Use it just for testing environments! Do not use for production systems.

Features:
1. Simple, easy to use interface.
2. TekPhone Supports (Only) G.711 A - Mu law codecs and RFC 2833 for DTMF digit delivery.
3. UPnP for NAT traversal is supported. You can also set external IP address manually.
4. TekPhone can record incoming audio if away mode selected. You can specify your own welcome message.
5. Tekphone also supports ENUM (RFC 3761).

To install TekPhone, extract contents of TekPhone.zip to a temporary directory, run Setup.exe from the distribution. Uninstall previous version if you upgrade from an earlier version.

To uninstall TekPhone, double click TekPhone icon at "Add or Remove Programs" from Control Panel.

Running:
1. Run TekPhone from Start / Program Files / TekPhone.
2. Select IP address to be listened on the settings tab.
3. Logging is optional.
4. Set SIP endpoint ID (Username) and SIP Domain.
5. If you save the configurations changes, they take effect immediately.

Installation
Unzip "TekPhone.zip" and click "Setup.exe" comes with the distribution. Follow the instruction of setup wizard. Setup will install TekPhone, add a shortcut for TekPhone to desktop and the start menu.

Configuration
Run TekPhone by double clicking TekPhone.exe in the application directory. TekPhone selects first available IPv4 address to listen. TekPhone also checks if it is installed behind an UPnP supported NAT gateway. TekPhone also adds a reverse mapping for incoming UDP connections automatically (Default UDP port 5090).

The license of this software is Freeware, you can free download and free use this internet phone software.