On Providing Soft-QoS in Wireless Ad-Hoc Networks

In this paper we present a soft–QoS scheme for wireless networks based on the well–known ad–hoc distance vector (AODV) routing algorithm. We show how AODV may be easily modified to support (in a statistical sense) QoS provisioning over multihop wireless networks. Basically, each route discovery packet gathers an estimate of the delay and bandwidth along the path from source to destination. Then, according to the soft–QoS requirements of the application, the destination chooses the connection path (if any) which best satisfies the service constraints. The proposed scheme does not rely on priority–based scheduling schemes or complex resource reservation mechanisms. Soft–QoS guarantees are, instead, provided by means of a statistical and distributed Call Admission Control algorithm. In order to verify the effectiveness of the proposed algorithm, we finally apply the scheme to a Bluetooth scatternet scenario and provide simulation results.