Hierarchical Grown Bluetrees (HGB): An effective topology for Bluetooth scatternets

Bluetooth is a promising technology for short range wireless communication and networking, mainly used as a replacement for connected cables. Since the Bluetooth specification only defines how to build piconet, several solutions have been proposed to construct a scatternet from the piconets in the literatures. A tree shaped scatternet is called the bluetree. In this paper, we present a method to generate the bluetree hierarchically; namely, the nodes are added into the bluetree level by level. This kind of Hierarchical Grown Bluetree (HGB) topology resolves the defects of the conventional bluetree. During growing up, HGB always remains balanced so as to preserve shorter routing paths. Besides, the links between siblings provide alternative paths for routing. As a result, the traffic load at parent nodes can be greatly improved and only two separate parts will be induced if a parent node is lost. The Bluetooth network therefore achieves better reliability.