An Energy Efficient Hybrid Routing Protocol for Bluetooth Radio Networks

[[abstract]]行動裝置的發展趨勢是輕，薄、短、小、伴隨而來的問題是有限的電源必須做最好的應用。藍芽無線網路依每個裝置的省電機制可分為(1)全部裝置皆Active的；(2)部分裝置Active,部分裝置Power Saving的PABN及(3)全部裝置皆為Power Saving的PSBN三類。 本篇論文的目的是在PABN及PSBN上發展省電的Routing Protocol為了協助Routing Protocol之建立，本論文首先將介紹三個支援 Routing Protocol的程序；第一個程序為Internal State Scheduling：主要目的是對Bluetooth裝置內部State的變化進行規劃使得整個Protocol各個State的Latency能愈短愈好；第二個程序是：Route Table Exchange Procedure，這個Procedure的目的是透過正常的連線建立程序讓兩個Bluetooth Device能完全交換已知的Routing Information及找出新的鄰居；第三個程序是：Enhanced Page Procedure,對於已知BD_Addr及Clock Offset的鄰居可以Page Procedure建立Connection，但由於Piconet並未持續建立導致Clock Drift問題的發生，透過Enhanced Page Procedure可有效的修正Clock Drift 問題。 我們在PSBN上提出的Routing Protocol主要是利用Local Route Table的查詢來找尋Destination.當Destination不存在時，才以Flooding的方式找Destination；但因為PSBN並未Maintain Piconet架構，因此需使用Enhanced Page Procedure傳遞RREQ封包.當Destination找到時，再由Destination建立由Master/Slave Relay所構成的Route進行資料傳送；另一方面,在PABN上，我們提出一套Backbone建立的法則，Backbone上的的節點負責Route Information Delivery ，因此Route Discovery的時間可大幅縮短，但因為Backbone上的每點都有可替代的Devices可替換的任務，因此網路的Life Time可延長。 由實驗結果顯示我們所提出具省電效能藍芽繞徑協定能有效延長整個網路的生命週並使Delay時間縮短及形成一個快速回應的通訊環境，整個系統的效能可因此大幅提升。[[abstract]]The development of mobile device technology aims at a ligher, thinner, shorter, and smaller product. The associated problem of mobile device is limited power. According to the power saving mechanism in each device, the bluetooth networks can be categorized into the following classes. The first class is active Bluetooth network (ABN), in which all devices are avtive. The second class is partial active Bluetooth network (PABN), in which some devices are in active mode and the remaining devices are in power saving mode. The third class is power saving bluetooth network (PSBN), in which all devices are in power saving mode. The objective of this thesis is to develope energy efficient routing protocol in both PABN and PSBN. In this thesis, we will first introduce routing support procedures on which routing protocol can be easily constructed. To reduce the latency of network construction, the first procedure is internal state scheduling. The second proceure is route table exchange procedure through which the neighboring information can be collected. The last procedure is enhanced page procedure. To resolve the clock drift problem, the proposed page procedure tries to catch the right channel such that a page procedure can be completed without the maintainance of active link. In PSBN, the proposed protocol query local route table to find destination address. If the information is not available, then a flooding procedure is initiated. Due to the piconet structures are not constructed in PSBN, the enhanced page procedure is requried to establishment links between two devices. When the destination device received RREQ packet, it will reply a RREP packet to source and construct scatternet based on the forwarding path of RREQ packets. In the constructed scatternet, all intermediated node are master/slave relays. On the other hand, we also propose a routing protocol in PABN. In PABN, a backbone path is maintained such that routing information among devices can be forwarded and exchanged smoothly. The advantages of routing protocol in PABN is smaller latency and longer network lifetime. The proposed routing protocols are verified by experimental results. According to experimental results, the latency is reduce, the network lifetime is increased. Thus, a better performance of system can be achieved