Adaptive Management of Bluetooth Slave/Slave Bridge

This paper discusses the minimization of end-to-end delays in a small Bluetooth scatternet with a Slave/Slave bridge. We assume that both piconets operate under exhaustive scheduling policy, that slaves generate packet bursts, that burst arrivals follow Poisson distribution, and that the size of packet bursts follows geometric distribution. Using the theory of queues with vacations, we investigate the possibility of choosing scatternet parameters so as to minimize the aforementioned delays. We show that the minimization of delay should use the time interval between bridge exchanges in order to minimize inter-piconet traffic, since the intra-piconet traffic delay is less sensitive to the actual value of the time interval between bridge exchanges. Then, we present a load adaptive algorithm that would change this time dynamically, and show how the end-to-end delay is indeed minimized in this manner. Simulation results confirm that the algorithm is able to achieve minimum endto-end delay for inter-piconet traffic under a wide range of traffic loads. Keywords— Bluetooth scatternet, Slave/Slave bridge, performance evaluation, queueing theory, delay minimization