A flexible relay selection technique for Bluetooth scatternet

Bluetooth is a low power, short range and promising wireless technology but has limited resources. Bluetooth devices are connected in an ad hoc fashion in a piconet and their communication approach is driven by a master-slave configuration. The Bluetooth basic communication unit is called a piconet. A larger Bluetooth network can support multiple piconets, where different piconets are connected through a common node called a relay. A relay node provides connection among different piconets. Relay nodes use different hopping patterns for different piconets and forward data from one piconet to another. Multiple connected piconets are called a scatternet; a scatternet may have multiple relays. Unnecessary inflexible relay selection may decrease network performance and increase scheduling overhead. Moreover, position of a relay node has also impact on Bluetooth scatternet performance. Bluetooth current specification describes how to build a piconet, but the construction of a scatternet and inter-piconet communication has been left out. This paper presents a Flexible Relay Selection Technique (FRST), which reduces unnecessary relays by reducing relay reduction control overhead. Empirically, through simulations, the proposed FRST has reduced the control overhead, transmission delay and network stability. The simulation results have demonstrated an improvement on networks. All these results are evidence that the FRST has outperformed existing protocols for the same issue. Hence, the inefficiency of the inter-piconet scheduling in a scatternet of a Bluetooth network can be resolved by implementing the proposed FRST.