An Signal-Strength-Based Reliable QoS Route Selecting Scheme In Mobile Ad Hoc Networks

Mobile Ad Hoc Network (MANET) is a kind of self-organized communication network without fixed infrastructures. Because of its efficient self-organization characteristic, supporting dynamic topology structure and multi-hop transmission technology, it is widely applied in the fields of emergency environments such as military, traffic and accident environment as well as civil wireless data communication. With the development of MANET and the popularity of multimedia technology, people has not been satisfied with MANET for data transmission only, but to offer more types of services, such as form pure data, voice and some kind of limited video transmission to the data, voice, and image integrated transport, so this requires MANET can provide some QoS guarantee. While factors of mobility, interference of channels and energy consumption, make MANET topology structure obtain perform of changing dynamically, which brings great challenge to design the routing protocols to support QoS requirements that has been the hot sports of MANET research and development.The Mobile Ad Hoc Network conception, features and structure were introduced firstly in this paper, and tow types of MANET protocols were expatiated and analysed subsequently, then two typical routing protocols of proactive and reactive protocols were introduced and a series of comparisons and discussions were conducted by simulation. Then, some typical of the existing MANET QoS routing protocols are studied and compared.On the base of analysis of existing relevant research at home and abroad, on how to provide routing protocols with QoS guarantee in MANET are studied in-depth. The unreliable connection caused by nodes moving dynamically and impact of limit bandwidth resource on quality of service in MANET have been alleviated by an effective Signal-Strength-based reliable QoS route selecting scheme (SSRQ) in mobile Ad Hoc Network on the base of Ad-hoc On-Demand Distance Vector Algorithm (AODV) proposed in this paper. The route reliability can be estimated by received signal strength to select more reliable link that satisfies QoS requirement by adding relative information to RREQ/RREP. As SSRQ agreements to select routes based on path reliability, thus greatly reducing the number of broken links due to the host motion.Simulation of network communicating performance between SSRQ and traditional AODV has been done in this paper. In random network model, some metrics of packet successful delivery rate, control packet overhead and average end-to-end delay of data packets has been simulated and analysed in the environment with mobility, number of source nodes and network size can be changed. NS2 based simulation indicates that the reliable route selecting scheme presented in this paper shows obvious superiority to traditional AODV in packet successful delivery rate and average end-to-end delay but not bringing more control overhead.