Indian Journal of Science and Technology

Abstract

Background/Objectives: Improving performances of routing protocols which use the multipath scheme and the hop count routing metric in ad hoc networks in order to satisfy quality of service requirements of different application traffics. Methods/Statistical Analysis: This paper proposes a technique to estimate the values of delay and packet loss ratio of MAC layer’s links by using the ETX technique and the service time calculation of DCF in CSMA/CA principle, respectively. After that, these values are combined with the weights which are obtained from application traffic classification using cross-layer approach to establish new routing metrics. These metrics are suitable for Quality of Service (QoS) requirements of applications. Findings: Traditional multipath routing protocols operate only in Network layer and utilize a static routing metric which leads them to be unable to give route priority to different traffic classes from Application layer. After applying the suitable dynamic routing metrics of delay and packet loss ratio for application traffic classes when implementing new multipath routing protocol named QCLR in NS2 simulator, the results of performance evaluations show that the performance of proposed protocol higher than AOMDV protocol regarding to higher throughput, lower overhead traffic, higher packet delivery ratio and smaller end-to-end delay for both of Class 1 and Class 2 traffics. Applications/ Improvements: Improving quality of routing service for applications which have different traffic classes, especially for multimedia applications.

Keywords: Ad hoc, Cross-layer, Packet Loss Ratio, QoS, Routing Metric, Service Time