Blue-Park: Energy-efficient operation of Bluetooth networks using park mode

Bluetooth provides wireless networking among proximate nodes. The Bluetooth nodes are usually battery-powered, which puts a strong demand on the design of energy-efficient network structures. In the conventional piconets and scatternets, the roles of master, slave, and bridge are assigned to the nodes in a semi-static manner. This produces unfairness, since the master and bridge roles have higher activity and thus higher energy consumption. The logical piconet/scatternet structure decreases the energy efficiency by requiring packet forwarding even when a direct wireless link is possible. In this paper, we propose Blue-Park, a flexible networking structure that achieves energy efficiency and fairness, without requiring change to the Bluetooth Specification. Blue-Park utilizes the Bluetooth park mode and can be described as a self-referencing structure, where each node parks all the other nodes as a master. The packets are exchanged between nodes with dynamic park/unpark procedures, which results in dynamic role assignment. We evaluate the Blue-Park in two scenarios – comparison with a piconet and comparison with a scatternet among nodes that are physically within a single hop. The simulation results show that, when the incoming traffic at each device is bursty, in both scenarios Blue-Park can achieve higher energy efficiency and lifetime. Furthermore, the delay is not increased significantly due to the dynamic link establishment.