Design, Modeling and simulating an QoS managed IP based public voice network

Abstract

In recent years, the Internet has proven its ability to carry real-time data, including voice. Today, a small amount of voice traffic has already been diverted from the Public Switched Telephone Network (PSTN) to the Internet. This Dissertation report presents a brief idea about the provision of interoperable services between IP based telephone system and the PSTN and how to achieve the same Quality of Service (QoS) in the IP based telephone system. The Voice network (PSTN) is design for voice and it is optimized to the perfect voice quality. But IP network is a best effort and it is more suitable for the data communication (Non time sensitive application). The moment we put the voice into the IP based network it will effect by delay, delay variance, echo, degraded voice quality and missing of some voice part.

In this project we are analyzing how to over come above issues and how to implement a IP based voice network with a same voice quality as traditional PSTN. In this IP based telephone system user can have either a IP phone or a soft phone to make a call either to another IP phone or a soft phone or a PSTN analog phone and vice versa.

The goals of this project are to reduce the capital cost for the separate voice network, several additional features can obtain from a IP based voice network such as voice messages, call forwarding and CLI, and reduce the maintenance cost for the voice network.