VoIP/SIP client (softphone) for Windows

When looking for a SIP and media stack I've spotted libre/librem/baresip from creytiv.com. It has I believe pretty unique combination of simplicity, completeness and most of all permissive BSD-style license allowing commercial and closed-source derivatives.

Quick specification

Note: page is organized in chronological way. This specification refers to latest version.

Console application

Minimal subset (no video support, no codecs besides G.711, just the essentials for voice calls) of libre/librem/baresip as a console application built with Turbo C++ 2006 Explorer. If you're not a Borland products user stay with original source code that can be used with i.e. VC++ 2003.
bsip_tc_20111215.7z - source only

GUI SIP client

SIP client with graphical user interface built upon re/rem/baresip stack. Feature set is very limited, but whole project is self-contained and easy to compile - no external dependencies. GUI is using simplest possible model: single registration account and single call at a time, but application is portable and using configuration from a local JSON file, so many instances can be run simultaneously with different configurations. Each instance takes ~1.8 MB of disc space (including wave files with signals such as ringing).
tSIP: simple VoIP/SIP application

mini-HOWTO

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