- 期刊
An Improved Resource Allocation Scheme for VBR VoIP Support in Ad Hoc Networks Connected to Fixed IP Networks
並列摘要
This paper analyzes how to provide end-to-end Quality of Service between nodes in a mobile ad-hoc network and a fixed IP network that supports Differentiated Services. The ad-hoc network incorporates the Stateless Wireless Ad Hoc Networks (SWAN) model to support service differentiation. SWAN uses local rate control for best-effort traffic and sender-based admission control for real-time traffic. Before the admission control process has finished, a real-time flow is treated as best-effort traffic and it is delayed by a shaper. We introduce a modified version of SWAN named FA-SWAN (Fast Admission-SWAN) where new real-time flows bypass the best-effort traffic shaper during the admission control process. Only after a real-time session is rejected as such, the traffic will be considered as best-effort and will have to be rate controlled. We have evaluated the capacity of the two algorithms to support VBR Voice over IP (VoIP) applications and CBR as background traffic. The performance of VoIP is shown through simulations. The results indicate that the modifications improve the performance of the voice application in comparison with the original SWAN. Furthermore, VoIP traffic is effectively controlled and is not influenced by the best-effort traffic load. Even under heavier CBR traffic the Quality of Service specifications for VoIP are satisfied.