Practical VoIP Using VOCAL [ILLUSTRATED] Luan Dang, Cullen Jennings, David Kelly

While many books describe the theory behind Voice over IP, only Practical VoIP Using VOCAL describes how such a phone system was actually built, and how you too can acquire the source code, install it onto a system, connect phones, and make calls. VOCAL (the Vovida Open Communication Application Library) is an open source software project that provides call control, routing, media, policy, billing information and provisioning on a system that can range from a few test phones to a large, multi-host carrier grade network supporting hundreds of thousands of users. VOCAL is freely available from the Cisco Systems-sponsored Vovida.org community web site (www.vovida.org). Because VOCAL is open source, you can look "under the hood" to the base code and protocol stack levels and discover not only how the system works, but also how common problems are being worked out in the development environment. You can take this system to another level by implementing a feature or functionality that no one"s thought of before. Это и многое другое вы найдете в книге Practical VoIP Using VOCAL [ILLUSTRATED] (Luan Dang, Cullen Jennings, David Kelly)