Comprehensive Survey on Speech Quality Adaptation Invoice Over Internet Protocol (VOIP)

Voice over Internet Protocol (VoIP) for telephony network is becoming an important tool for voice communication. It is one of the prominent and fastest growing telecommunication service based on an Internet protocol suite. VoIP enables the users to use the Internet as the transmission medium for voice communication This survey aims to give a comprehensive review of the current state-of-the-art research on speech quality adaptation of VoIP systems at the application layer. It should be especially helpful for new researchers in the field to get a big picture of the diverse QoS control methods for VoIP and their effectiveness in improving speech quality. Pointers to relevant works in this field are also provided for further reference.