Bluetooth是一種新的短距離的無線通訊技術，裝有Bluetooth晶片的device可以在10公尺左右的範圍內進行聲音及資料的傳輸和交換，透過Bluetooth所形成的網路最小單元稱為Piconet，每個Piconet是由1個Master及最多7個Active Slave所組成，同時參與多個Piconet的Slave稱為Bridge，不同的Piconet則可以透過Bridge的連結而形成Scatternet。
在Scatternet的環境中，諸如具有QoS要求的通訊服務及跨Piconet的routing服務，在某段時間內source及destination有其需求的通訊量，因此，資料的傳送及流量的需求具有Temporal Locality[14]的特性，未來的流量與先前資料傳送的歷史記錄相關，為了避免Bridge在不同Piconet間切換所產生的衝撞，一個好的scheduling方法，必須考慮Temporal Locality的特性，並同時滿足Intra-piconet及Inter-piconet的不同需求，協調不同Piconet之間時槽安排的衝撞問題。在這篇論文中，我們提出了一個Scheduling Protocol，其能夠避免Piconet內資料傳送時的挨餓問題(starvation)，並依傳送資料的流量不同，使time slot資源能充分安排給傳送資料的需求者，以增加Piconet內的throughput，至於Piconet間因協調不一致而產生的衝撞問題，我們所發展的Scheduling Protocol亦能有效解決，並依照資料傳送的歷史記錄來排程，在公平性、QoS要求、環境品質、有限電量、有限buffer size等因素的考量下，使各 Master能有效運作於我們所研發的Scheduling Protocol，實驗結果顯示，我們所研發的協定能依各deivce的資料通訊量需求，適當的其進入省電模式、polling順序及服務時間，並能有效解決Inter-piconet間規劃衝突的問題，進而使Scatternet達到高效率及高正確率的資料傳輸。

Bluetooth is a new technology for low-power and short-range wireless communication. Devices with Bluetooth chip can exchange data or voice packets within 10 m. The basic network unit in Bluetooth is called a piconet. Each piconet is composed of one master and at most seven active slaves. A slave that participates in multiple piconets can serve as bridge and forwards traffic between neighboring piconets. Different piconets can form a large network called a scatternet.
In a scatternet environment, routing is necessary because service provider and service consumer may not in the same piconet. Data transmission must be accomplished by bridge. It will cause a collision of bridge in scheduling. In this paper, we proposed a scheduling protocol which can (1) work in both intra-piconet and inter-piconet (2) avoid collision of bridge in scheduling (3) efficiently allocate bandwidth to all devices. The simulation results show the performance of the Bluetooth network is improved when using our proposed protocol.

Reference
[1]Specification of the Bluetooth System, Ver. 1.1 Febrary 22, 2001,
http://www.bluetooth.com
[2]Capone, Gerla, and Kapoor, "Efficient Polling Schemes for Bluetooth
Picocells," Proceedings of ICC 2001, Helsinki, FD, June 2001.
[3]Abhishek Das, Abhishek Ghose, Ashu Razdan, Huzur Saran, and Rajeev
Shorey "Enhancing Performance of Asynchronous Data Traffic over the
Bluetooth Wireless Ad-hoc Network," Proceedings of IEEE INFOCOM 2001,
Alaska, USA, April 2001.
[4]Simon Baatz, Matthias Frank, Carmen K|hl, Peter Martini, and Christoph
Scholz, "Adaptive Scatternet Support for Bluetooth using Sniff Mode,"
Proceedings of the 26th Annual Conference on Local Computer Networks, LCN
2001, Tampa, Florida, November 2001.
[5]Kalia M, Bansal D, and Shorey R, "MAC Scheduling and SAR Policies for
Bluetooth: A Master Driven TDD Pico-cellular Wireless System," in Mobile
Multimedia Communications, 1999. (MoMuC ''99). 1999 IEEE International
Workshop , pp. 384 -388, 1999.
[6]Raffaele Bruno, Marco Conti and Enrico Gregori, "Wireless Access to Internet
via Bluetooth: Performance Evaluation of the EDC Scheduling Algorithm"
workshop on Wireless mobile internet, pp. 43-49, July 21, 2001.
[7]Manish Kalia, Deepak Bansal and Rajeev Shorey, "Data Scheduling and SAR for
Bluetooth MAC," IEEE Vehicular Technology Conference (VTC), May 2000.
[8]N. Johansson, U. Korner and P. Johansson, "Performance Evaluation of
Scheduling Algorithms for Bluetooth," in Broadband Communications :
Convergence of Network Technologies, Edited by Danny H.K. Tsang and Paul
J.Kuhn, Kluwer Academic Publishers, pp 139-150, 2000.
[9]Andras Racz, Gyorgy Miklos, France Kubinszky, and Andras Valko, "A pseudo
random coordinated Scheduling algorithm for Bluetooth scatternets,"
Proceedings of the 2001 ACM International Symposium on Mobile ad hoc
networking and computing (MobiHoc), pp. 193-203, 2001
[10]N. Johansson, F. Alriksson, and U. Jonsson, "JUMP mode - a dynamic window-
based Scheduling framework for Bluetooth scatternets," Proceedings of the
2001 ACM International Symposium on Mobile ad hoc networking and computing
(MobiHoc), pp. 204-211, 2001
[11]Niklas Johansson, Maria Kihl, Ulf Kvrner, and Lund University, "TCP/IP over
the Bluetooth Wireless Ad-hoc Network," Networking 2000, May pp. 14 - 19,
2000, Paris, France
[12]N. Johansson, U. Koerner, and L. Tassiulas. "A Distributed Scheduling
Algorithm for a Bluetooth Scatternet," The Seventeenth International
Teletraffic Congress, ITC’17, September 24-28, 2001, Salvador da Bahia,
Brazil.
[13]Bhagwat, P. and Segall A., "A Routing Vector Method (RVM) for Routing in
Bluetooth Scatternets," in Mobile Multimedia Communications, 1999.
(MoMuC ''99). 1999 IEEE International Workshop on, pp. 375 -379, 1999.
[14]Cherkasova L. and Ciardo G.. "Characterizing Temporal Locality and Its
Impact on Web Server Performance," in Computer Communication and Networks,
2000. Proceeding. Ninth International Conference on 2000.
[15]Min, CS Kim, H. Shin, and DK Jeong, "An Adaptive Segmentation Scheme for
the Bluetooth-based Wireless Channel," in Proceedings of the IEEE
International Conference on Computer Communications and Networks
(ICCCN ''01), pp. 440-445, 2001.
[16]Wensheng Zhang, and Guohong Cao, "A Flexible Scatternet-wide Scheduling
Algorithm for Bluetooth Networks," in Performance, Computing and
Communication conference ,2002 . 21st.
[17]Bluetooth Assigned Numbers Versions 1.1 , February 22, 2001.
[18]Salonidis T, Bhagwat P and Tassiulas, L, "Proximity Awareness and Fast
Connection Establishment in Bluetooth," MobiHOC. 2000 First Annual Workshop
on , 2000 , pp. 141 -142