Bluetooth is reputed as a wireless networking technology capable of forming ad-hoc networks between digital devices. In particular, the Bluetooth scatternet will be an essential part of the fully distributed ad-hoc networks. However, scatternet is not fully described in the Bluetooth specification. This has been the topic of discussion among researches in relation to the formation algorithm, scheduling scheme, etc. Most of the proposed algorithms reported in past researches on scatternet formation are too large and complex to be implemented in a real commercial Bluetooth hardware. Therefore, the verifications of the proposed algorithms reported in past researches were done through only simulations. In addition, the formation process takes too long and these past researches had been conducted only in static environment where no node enters or leaves the scatternet. In this paper, therefore, we propose a new scatternet formation algorithm called Node Ring Scatternet (NRS), emphasizing on two aspects, i.e. implementation and dynamic property of the algorithm. The algorithm is very simple and compact and is verified to be easily implementable in a real commercial Bluetooth device. For the dynamic properties, the NRS entails relatively short formation delay and a reformation algorithm in a dynamic environment was designed. Therefore, the network of the NRS can be scalable and flexible. In addition, a new protocol called SFMP (Scatternet Formation & Management Protocol) was designed and is presented herein. Using this protocol, the NRS algorithm was implemented in a real Bluetooth device, and the performance was verified through hardware experiments. Based on the experimental results, it was found that the NRS composed of up to 20 nodes is formed and the proposed algorithm has shown improvement in terms of formation delay, formation probability and reformation.

It is recognized in Japan that reformation of the national research institutions is urgently necessary. Present situation and constraints are shown and the action items are discussed.