Bluetooth scatternet formation: Criteria, models and classification

Bluetooth ad hoc networks are constrained by a master/slave configuration, in which one device takes the role of master and controls the communication with the slave devices. Piconets are small Bluetooth networks containing one master and up to seven active slave devices. In order to build larger topologies, called scatternets, the piconets must be interconnected. Scatternets are formed by allowing certain piconet members to participate in several piconets by periodically switching between them. Due to the fact that there is no scatternet formation procedure in the Bluetooth specification, numerous different approaches have been proposed. We discuss criteria for different types of scatternets and establish general models of scatternet topologies. Then we describe the state-of-the-art for Bluetooth scatternets and compare and contrast the approaches.