A Soft-QoS Scheduling Algorithm for Bluetooth Piconets
Andréa Zanella, Daniele Miorandi, Silvano Pupolin, Cristian Andreola · 2003
In this paper we present a scheduling scheme for supporting soft‐QoS in Bluetooth piconets. The slave nodes negotiate with the master the target QoS level, expressed in terms of minimum bandwidth and maximum delay. The QoS requirements come along with a soft‐index that determines the degree of tolerance on the target QoS that a slave is ready to accept for the intended connection: the higher the soft‐index, the looser the QoS requirements. The algorithm keeps a dynamic estimation of the satisfaction of each node, defined as the fraction of packets that satisfy the QoS requirements. Accordingly, the master dynamically tunes the slaves priorities. Such priorities are then used to decide which slave will be polled at the next available slot. The effectiveness of the proposed algorithm is supported by numerical simulations, which show how the use of the soft-indexes and the dynamic estimation of the users satisfaction lead to a more efficient use of the system resources.