QoS Guaranteed Voice Traffic Multiplexing Scheme over VoIP Network Using DiffServ

Abstract

The current VoIP transfer methods using low bit rate codes such as G.723.1 and G.729 are still very inefficient due to its small payload size in comparison with its large overhead size. Besides, the traffic load on the access routers tends to geometrically increase when the incoming traffic flows of short packets increase. These factors cause problems such as delay, jitter, and packet loss, which seriously deteriorate the voice quality. We propose a new efficient voice traffic multiplexing scheme with guaranteed end-to-end QoS between VoIP access routers using differentiated services (DiffServ). The newly defined RTP/UDP/IP packets, namely, L_packet (long packet) using DiffServ are multiplexed at ingress routers for offering real-time communication services in very high-speed backbone network. We analyze the performance of proposed scheme for various bit rate type traffics and simulate the call blocking probability. It shows that the proposed scheme quite satisfactorily guarantees the end-to-end QoS requirements.