Journal of Computer Science and Technology

, Volume 20, Issue 2, pp 276–281 | Cite as

RWBO(p d w): A Novel Backoff Algorithm for IEEE 802.11 DCF

  • Yun LiEmail author
  • Ke-Ping Long
  • Wei-Liang Zhao
  • Feng-Rui Yang


The Probability Distribution of Slot Selection (PDoSS) of IEEE 802.11 DCF is extremely uneven, which makes the packet collision probability very high. In this paper, the authors explore how to make the stations select the slots uniformly, and give an RWBO(p d , w) algorithm for 802.11 DCF to make the PDoSS even and decrease the packet collision probability. A Markov model is given to analyze the PDoSS of RWBO(p d , w). The performance of RWBO(p d , w) is evaluated by simulation in terms of saturation throughput and packet collision probability. The simulation results indicate that RWBO(p d , w) can decrease the packet contention probability to a large extent, and utilize the channel more efficiently as compared to the 802.11 DCF. Moreover, the relation between saturation throughput and walking probability (p d ), the relation between saturation throughput and contention windows (w), the relation between packet collision probability and walking probability (p d ), and the relation between packet collision probability and contention windows (w) are analyzed. The analysis indicates that RWBO(p d , w) has some remarkable features: its saturation throughout keeps high and packet collision probability keeps very low (under 0.1) in a large range of p d and w, which allow users to configure p d and w more flexibly.


IEEE 802.11 DCF PDoSS random walking BackOff Markov chain model 


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Copyright information

© Springer Science + Business Media, Inc. 2005

Authors and Affiliations

  • Yun Li
    • 1
    • 2
    Email author
  • Ke-Ping Long
    • 1
  • Wei-Liang Zhao
    • 1
    • 3
  • Feng-Rui Yang
    • 1
  1. 1.Special Research Centre for Optical Internet and Wireless Information Networks Chongqing University of Posts and TelecommunicationsChongqingP.R. China
  2. 2.National Defense Key Lab of Anti-Interference Communication TechnologyUniversity of Electronic Science and Technology of ChinaChengduP.R. China
  3. 3.School of Electronic EngineeringBeijing University of Posts and TelecommunicationsBeijingP.R. China

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