在這篇論文裡，我們提出一個稱為BRQ (Bandwidth-Reservation QoS scheme)的機制，BRQ是一個適用於Ad Hoc無線網路環境，且支援QoS的MAC層機制。
不同於以往大部分的方式是在傳送封包前的backoff或IFS狀態中作控制(如IEEE 802.11e)，BRQ是利用兩個不同頻率，不會互相干擾的頻道，分別負責傳送RTS、CTS跟data、ACK，並且在RTS、CTS中加入一些訊息告知週遭的mobile stations，以便高優先權的資料可以預先預約頻寬。如此不僅可以達到實現QoS的目的，也同時解決了以往傳統的機制無法解決的alternate blocking problem。
　　而由於BRQ與以往IFS或backoff time interval相關的QoS機制在實現方法上並無衝突，因此我們在論文最後的模擬中，除了將我們提出的BRQ與IEEE 802.11e的效能作比較外，更將BRQ與IEEE 802.11e作整合，證明兩機制整合的可行性，以及整合後可以達到更高的效能。

This paper proposed BRQ (Bandwidth-Reservation QoS scheme) for mobile Ad-Hoc wireless network. Unlike many schemes about IFS or backoff time interval of DCF in IEEE 802.11, BRQ uses the bandwidth reservation mechanism to support QoS. Because of the compatibility of BRQ with other schemes, we believe that BRQ scheme can achieve higher performance by integrating with other schemes.
We evaluate the performance of BRQ, DCF in IEEE 802.11, EDCF in 802.11e, and BRQ+ (the combined scheme of BRQ and EDCF) in terms of their differentiation capability, network throughput, and average end-to-end delay. The simulation results demonstrate the effectiveness of the BRQ scheme and show that the BRQ+ scheme can achieve higher performance by integrating BRQ and EDCF.

Chapter 1 Introduction 1
Chapter 2 Background & Related Works 3
2.1 QoS Schemes about IFS and Backoff Time Interval 3
2.1.1 Background of IEEE 802.11 3
2.1.2 QoS Schemes about IFS and Backoff Time Interval of IEEE 802.11 4
2.1.3 Service Differentiation Mechanisms for IEEE 802.11e 6
2.1.4 Busy Tone Priority Scheduling (BTPS)Scheme 8
2.2 Alternate Blocking Problem 10
2.3 Other Related Works 12
2.3.1 WRT (Wireless Real-Time)-Ring Protocol 12
2.3.2 PBC (Prioritized Binary Countdown) Scheme 13
Chapter 3 Bandwidth Reservation Scheme 15
3.1 Assumptions 15
3.2 Idea and Point of View 16
3.3 Bandwidth Reservation Scheme 17
3.3.1 Packet Format of BRQ 17
3.3.2 Reservation Table of BRQ 17
3.3.3 BRQ (Bandwidth Reservation QoS) Scheme 18
Chapter 4 Simulations and Simulation Results 24
4.1 Alternate Blocking Problem 24
4.1.1 Simulation Environment of Alternate Blocking Problem 24
4.1.2 Simulation Results of Alternate Blocking Problem 25
4.2 Service Differentiation 27
4.2.1 Simulation Environment of Service Differentiation 28
4.2.2 Simulation Results of Service Differentiation 29
4.3 Comparison of BRQ+ and IEEE 802.11e 30
Chapter 5 Conclusion & Future Work 34
Reference 35

[1] Hannan Xiao, Kee Chaing Chua, W. Seah, A. Lo, “On Service Prioritization in Mobile Ad-Hoc Networks,” IEEE International Conference on Communications, Pages: 1900 - 1904, Vol. 6, 11-14 June 2001
[2] Imad Aad, and Claude Castelluccia, PLANETE project, “Differentiation mechanisms for IEEE 802.11,” IEEE INFOCOM 2001
[3] IEEE 802.11 WG, Draft Supplement to STANDARD for Telecommunications and Information Exchange Between Systems – LAN/MAN Specific Requirements – Part 11: Wireless Medium Access Control (MAC) and physical layer (PHY) specifications: Medium Access Control (MAC) Enhancements for Quality of Service (QoS), IEEE 802.11e/D2.0, Nov. 2001
[4] Anders Lindgren, Andreas Almquist, and Olov Schelén, “Quality of Service Schemes for IEEE 802.11: A Simulation Study,” IWQoS 2001
[5] Dr-Jiunn Deng, and Ruay-Shiung Chang, “A priority scheme for IEEE 802.11 DCF access method,” IEICE Transactions on Communications, Jan. 1999
[6] N. H. Vaidya, P. Bahl, and S. Gupta, “Distributed fair scheduling in a wireless LAN,” In Sixth Annual International Conference on Mobile Computing and Networking, Boston, Aug. 2000
[7] L. Donatiello, M. Furini, “Ad Hoc Networks: A Protocol for Supporting QoS Applications,” Proceedings. International , pp. 8, 22-26 April 2003
[8] Chi-Hsiang Yeh, Tiantong You, “A QoS MAC Protocol for Differentiated Service in Mobile Ad Hoc Networks,” International Conference on Parallel Processing, pages: 349-356, 6-9 Oct. 2003
[9] Chi-Hsiang Yeh, “The advance access mechanism for differentiated service, power control, and radio efficiency in ad hoc MAC protocols,” Proc. IEEE Vehicular Technology Conf., Oct. 2003
[10] http://pcl.cs.ucla.edu/projects/glomosim/
[11] Yuh-Chung Lin1,2, Wei Kuang Lai1, “Supporting QoS in Infrastructure Wireless Networks,” 1Department of Computer Science and Engineering, National Sun Yen Sen University, Kaohsiung, Taiwan, R.O.C., 2Department of Management Information System, Tajen Institute of Technology, Pingtung, R.O.C.
[12] Xue Yang, Nitin H. Vaidya, “Priority Scheduling in Wireless Ad Hoc Networks,” International Conference on Mobile Computing and Networking, pages: 71-79, 9-11 June. 2002
[13] M. Ogawa, T. Sueoka, T. Hattori, “Priority based wireless packet communication with admission and throughput control,” Proc. IEEE Vehicular Technology Conference, pages: 370-374, Vol.1, 15-18 May 2000
[14] Stefan Mangold, Sunghyuh Choi, Peter May, Ole Klein, Guido Hiertz, Lothar Stibor, “IEEE 802.11e Wireless LAN for Quality of Service,” http://www.comnets.rwth-aachen.de/publications/Abstracts/MangoldChoi_EW02.html, Dec 2003
[15] I. Aad and C. Castelluccia, “Differentiation mechanisms for IEEE 802.11,” Proceedings of IEEE INFOCOM’01, Anchorage, AK, April 2001
[16] IEEE, IEEE standard 802.11, Wireless LAN medium access control (MAC) and physical layer (PHY) specifications, 1997
[17] G. Bianchi, “Performance analysis of the IEEE 802.11 distributed coordination function,” IEEE Journal on Selected Areas in Communications 18(3), pages: 535-547, March 2000
[18] I. Stoica and H. Zhang, “Providing guaranteed services without per flow management,” Proceeding of ACM SIGCOMM’99 Cambridge, MA, August 1999
[19] N. Vaidya and P. Bahl, “Fair scheduling in broadcast environments,” Microsoft research technical report MSR-TR-99-61, August 1999
[20] N. Vaidya, P. Bahl and S. Gupta, “Distributed fair scheduling in a wireless LAN,” Proceeding of ACM MOBICOM’00, Boston, MA, August 2000
[21] Raj Jain, Gojko Babic, Bhavana Nagendra, C. Lam, "Fairness, Call Establishment Latency and Other Performance Metrics," ATM Forum/96-1173, August 1996