Energy efficient bridge management policies for inter piconet communication in Bluetooth scatternets

Bluetooth is a short-range wireless technology designed to connect various low power, resource constrained devices such as cameras, cell-phones, laptops, handhelds, etc. It is based on a master-slave paradigm where each master may connect and mediate with up to seven other active slaves in a network known as a piconet. These piconets may be inter-connected by one or more bridge slaves to form a scatternet. The bridges relay the inter-piconet traffic, by acting as switches. Usually, bridge nodes are always active, resulting in a constant usage of device resources, increase in packet delays and reduction in throughput. This would drain the energy of the bridge disproportionately, when compared to other nodes in the piconet. In this paper, we suggest two novel mechanisms that employ load-balancing techniques to conserve energy and share the responsibility of being a bridge among capable devices. By extensive simulations, we show that our bridge management policy leads to considerable improvement in energy savings and throughput.