FP/EDF versus FP/FIFO Local Scheduling and Probabilistic QoS Guarantees in a Bluetooth Piconet

Efficient communication in Bluetooth networks requires a good design of intra and inter-piconet scheduling solutions. Mathematical performance analysis of such solutions is very important. But, due to the complexity of the Bluetooth MAC, they have been analyzed mostly via simulations. We present analytic results regarding performance evaluation of a Bluetooth piconet, based on the M/G/l queue with batch arrivals and vacation times. We introduce a solution to support various traffics with QoS guaranties. We focus on two application constraints: the priority of a message and its end-to- end delivery deadline. We deal with two new local scheduling disciplines that we propose so far. The first is a combination of the class based priority queuing (PQ) and FIFO. The second is a combination of PQ and EDF. PQ is used between classes while FIFO and EDF are used within a class. We focus our interest to providing quality of service (QoS) guarantees to various classes of soft real-time applications by using a probabilistic approach. The waiting time distribution is then computed to obtain the probability that the response time doesn ´t exceed a given deadline.