Allowable propagation delay for VoIP calls of acceptable quality

Abstract

In VoIP network the primary factors affecting the voice quality are codecs, delay and any associated echo, and packet loss. In this paper, E-model is used to evaluate voice quality for end-to-end voice services over IP-based network. Assuming an acceptable voice quality objective is given on R(≥70) scale, the minimum amount of propagation delay available to the connection is called as allowable propagation delay. The allowable propagation delay is much more important factor than the one-way delay because the packetization and jitter buffer delay and transport delay are almost constant for the codec in VoIP networks. Thus, the allowable propagation delay budgets for each codec are provided in order to offer voice calls of acceptable quality in the IP telephony system.