跳到主要內容

臺灣博碩士論文加值系統

(44.200.194.255) 您好!臺灣時間:2024/07/20 15:01
字體大小: 字級放大   字級縮小   預設字形  
回查詢結果 :::

詳目顯示

我願授權國圖
: 
twitterline
研究生:潘慧珊
論文名稱:802.11e無線區域網路中有效率的輪詢機制
論文名稱(外文):An Efficient HCCA Scheduler for IEEE 802.11e Local Area Networks
指導教授:許俊萍許俊萍引用關係
學位類別:碩士
校院名稱:明新科技大學
系所名稱:資訊管理研究所
學門:電算機學門
學類:電算機一般學類
論文種類:學術論文
論文出版年:2008
畢業學年度:96
語文別:中文
論文頁數:60
中文關鍵詞:服務品質保證無線區域網路混合控制存取機制排程演算法
外文關鍵詞:Quality of Service802.11HCCAScheduling algorithm
相關次數:
  • 被引用被引用:0
  • 點閱點閱:175
  • 評分評分:
  • 下載下載:0
  • 收藏至我的研究室書目清單書目收藏:0
為了提供服務品質保證,訊務排程演算法是一項很重要的機制。IEEE 802.11標準中的Reference Scheme僅適用於CBR(Constant Bit Rate)訊務,FHCF排程演算法藉由佇列長度的預估來調適VBR(Variable Bit Rate)訊務的速率變動性。然而,估計誤差將造成頻寬不足與浪費,同時,輪詢順序也將影響CBR訊務之效能。因此本論文將提出一個新的HCCA排程演算法稱之為Dual-period排程演算法,將輪詢週期分成基本輪詢子週期與延伸輪詢子週期。基本輪詢子週期中以Reference Scheme為基礎來計算給予每個訊務的TXOP值,且優先輪詢CBR訊務,來保持Reference Scheme提供CBR訊務服務品質保證的優勢。對TXOP不足的VBR訊務,在延伸輪詢子週期中將再一次被輪詢,並公平地分配剩餘輪詢週期時間,來調適VBR訊務之變動性。本論文亦將藉由模擬程式的實驗結果來驗證Dual-period排程演算法能比FHCF有較好的效能。
To support the multimedia transmission with quality of service (QoS) guarantees in an IEEE 802.11e wireless local area network, it is crucial to design an efficient scheduling algorithm for HCF controlled channel access (HCCA). The reference scheme, proposed in the 802.11e, can only work well for traffics with strict constant bit rate (CBR). FHCF algorithm uses queue length estimations to capture the burst characteristic of variable bit rate (VBR) traffics. However, the estimation errors incur delay or waste bandwidth. Moreover, FHCF does not consider the polling order of traffics. It may affect the performance of CBF traffics in delay and jitter. In order to overcome the weakness of FHCF, this thesis proposes a new efficient HCCA scheduler, namely dual-period scheduling algorithm (DSA). The basic idea behind DSA is to divide a service interval into two subintervals: basic subinterval and extension subinterval. In the basic subinterval, CBR traffics always are serviced before VBR traffics, and the TXOP computation is referred to the specification of Reference Scheme. Upon finished the basic subinterval, the remaining service time of this service interval would be fairly allocated to those VBR traffics, with nonempty queue, in the extension subinterval. Simulation results show that DSA outperforms FHCF in terms of packet delay, jitter, and channel utilization.
摘 要......................................................i
Abstract...................................................ii
誌謝......................................................iii
目錄.......................................................iv
圖目錄.....................................................vi
表目錄....................................................vii
第一章 緒論.................................................1
1.1研究背景.................................................1
1.2研究動機與目的...........................................5
1.3論文架構.................................................6
第二章 802.11與802.11e相關研究之探討........................7
2.1 IEEE 802.11.............................................7
2.2 IEEE 802.11e............................................8
2.2.1IEEE 802.11e 訊框格式..................................9
2.2.2增強型分散存取機制....................................11
2.2.3混合型分散存取機制....................................13
2.3參考用演算法(Reference Scheme)........................14
2.4結論....................................................16
第三章 現有HCCA排程演算法之探討............................17
3.1 Scheduling Based on Estimated Transmission Times — Earliest Due Date(SETT-EDD)..............................17
3.2 Real-time HCCA Scheduler(RTH)........................18
3.3 FHCF排程演算法.........................................20
3.4討論....................................................22
第四章 Dual-period排程演算法...............................24
4.1概念....................................................24
4.2基本輪詢子週期(Basic subinterval).....................25
4.3延伸輪詢子週期(Extension subinterval).................26
4.4詳細步驟................................................27
4.5範例說明................................................32
第五章 模擬實驗與效能分析..................................35
5.1實驗分析與環境參數......................................35
5.2模擬實驗之評估指標......................................36
5.3實驗結果................................................36
5.3.1 DSA之overhead分析....................................36
5.3.2 FHCF與DSA之延遲......................................38
5.3.3 FHCF與DSA之延遲變異數................................39
5.3.4 FHCF與DSA之延遲抖動..................................39
5.3.5 FHCF與DSA之延遲滿足率................................39
5.3.6 FHCF與DSA之頻寬使用率................................40
第六章 結論................................................46
參考文獻...................................................47
[1] S.Keshav, An Engineering Approach to Computer Networking, Addision-Wesley Publishing Company, 1997.
[2] H. Jonathan Chao, Xiaolei Guo, Quality of Service Control in High-Speed Networks, Wiley, 2001.
[3] IEEE Computer Society “IEEE 802.11:Wireless LAN medium access control (MAC) and physical layer (PHY) specifications,” August 1999.
[4] IEEE Computer Society “IEEE 802.11:Wireless LAN Medium Access Control and Physical Layer Specifications. Medium Access Control (MAC) Quality of Service (QoS) Enhancements,” November 2005.
[5] L. Romdhani., Q. Ni, T. Turletti., “Adaptive EDCF: enhanced service differentiation for IEEE 802.11 wireless ad-hoc networks,” Wireless Communications and Networking, March 2003, pp. 1373 – 1378.
[6] Yang Xiao, Haizhon Li, “Evaluation of distributed admission control for the IEEE 802.11e EDCA,” IEEE Communications Magazine, Volume 42, Issue 9, Sept. 2004, pp. S20 - S24.
[7] Yang Xiao, H. Li, “Voice and video transmissions with global data parameter control for the IEEE 802.11e enhance distributed channel access,” Parallel and Distributed Systems, IEEE Transactions on, Volume 15, Issue 11, Nov. 2004, pp. 1041 - 1053
[8] Deyun Gao, Jianfei Cai, King Ngi Ngan , “Admission control in IEEE 802.11e wireless LANs,” IEEE Network, Vol. 19, Issue 4, July-Aug. 2005, pp. 6 – 13.
[9] N. Ramos, D. Panigrahi and S. Dey, “Quality of service provisioning in 802.11e networks: challenges, approaches, and future directions,” IEEE Network, vol.19, Issue 4, July-Aug. 2005, pp. 14 – 20.
[10] Q. Ni, “Performance Analysis and Enhancements for IEEE 802.11e Wireless Networks,” IEEE Network, vol.19, Issue 4, July-Aug. 2005, pp. 21 – 27.
[11] A. Grilo, M. Macedo, and M. Nunes, “A scheduling algorithm for QoS support in IEEE 802.11e networks,” IEEE Wireless Communications, vol. 10, no. 3, June 2003, pp. 36-43.
[12] C. Cicconetti, L. Lenzini, E. Mingozzi, and G. Stea., “Design and Performance Analysis of the Real-Time HCCA Scheduler for IEEE 802.11e WLANs,” Computer Networks, Vol. 51, Issue 9, February 2007, pp. 2311-2325.
[13] T. P. Baker, “Stack-based scheduling for real-time process”, Real-Time Systems, Vol. 3, Issue 1, March 1991, pp. 67-99.
[14] P. Ansel, Q. Ni, and T. Turletti., “FHCF: A Simple and Efficient Scheduling Scheme for IEEE 802.11e Wireless LAN,” Mobile Networks and Applications, vol. 11, no. 3, June 2006, pp. 391-403.
[15] A. D. Milhim and Y. C. Chen, “An Adaptive Polling Scheme to Improve Voice Transmission over Wireless LANs,” Computer Systems and Applications, May 2007, pp. 146 – 152.
[16] C. Cicconetti, L. Lenzini, E. Mingozzi, and G. Stea., “An efficient cross layer scheduler for multimedia traffic in wireless local area networks with IEEE 802.11e HCCA,” ACM SIGMOBILE Mobile Computing and Communications Review, July 2007, Vol. 11, Issue 3, pp. 31 - 46.
[17] D. Gozalvez, J. F. Monserrat, J. Gozalvez and L. Rubio, “An Efficient HCF Scheduling Mechanism in Mixed Traffic Scenarios,” Advanced Information Networking and Applications, Vol. 1, March 2005, pp. 479 – 483.
[18] T. D. Lagkas, G. I. Papadimitriou, P. Nicopolitidis and A. S. Pomportsis, ”Priority-Oriented Adaptive Control With QoS Guarantee for Wireless LANs,” IEEE Transactions on Vehicular Technology, vol. 56, Issue 4, July 2007, pp. 1761 – 1772.
[19] Wenpeng. Yuan, Guangxi Zhu, Gan Liu, and Di Wu, “Improvement on Network Capacity for Voice Services over HCCA,” Local Computer Networks, Oct. 2007, pp. 479 – 488.
[20] Z. A. Noh., T. Suzuki and S. Tasaka, “A Packet Scheduling Scheme for Audio-Video Transmission with IEEE 802.11e HCCA and its Application-Level QoS Assessment,” Asia-Pacific Conference on Communication, Aug. 2006, pp. 1 – 5.
[21] J. Stankovic et al., Deadline Scheduling for Real-Time Systems: EDF and Related Algorithms, Kluwer, 1998.
[22] “The Network Simulator-ns-2”, http://www.isi.edu/nsnam/ns/.
[23] “HCF/FHCF NS-2 implementation”, http://www-sop.inria.fr/planete/qni/fhcf/.
電子全文 電子全文(本篇電子全文限研究生所屬學校校內系統及IP範圍內開放)
QRCODE
 
 
 
 
 
                                                                                                                                                                                                                                                                                                                                                                                                               
第一頁 上一頁 下一頁 最後一頁 top
無相關期刊