The appearance of VoIP technology has now made feasible the use of data network for data, as well as voice communication. In this book, the protocol conversion between two different networks, packet scheduling and routing schemes for gateway selection has been introduced and also verified with Asterisk server. The recent trend for convergence of different access network technologies, market deregulation and emergence of dual-mode end-user devices allow the same destination to be reached by alternative paths and interfaces.Providing a good QoS in heterogeneous networks for irregular traffic...