A scalable and reliable QoS architecture (SRQA) for mobile ad-hoc networks

This paper proposes the design of a scalable and reliable QoS architecture for mobile ad-hoc networks, which consists of i) a multi-path routing protocol, ii) a call admission control (CAC) scheme and iii) a congestion control mechanism. The multi-path routing protocol utilizes erasure code techniques for producing replicated fragments for each packet, to enhance reliability. Important fragments can be sent through the paths with strong connectivity and high delivery probability. While it receives an assured number of fragments, destination can recover the original packet. In our CAC scheme, we admit the calls based on the bandwidth availability of the path. To avoid performance degradation due to mobility-triggered congestion, a congestion control mechanism has been developed. Once congestion occurs, the best effort traffic is rate controlled, to free bandwidth for the real-time flows. All these schemes together make the proposed QoS architecture scalable to large network size and mobility. By simulation results, we show that this architecture allows us to provide reliable QoS in ad-hoc networks, increases the available bandwidth, performs load balancing in the network and increases lifetime.