Previous researches have shown that Distributed Coordination Function (DCF) access mode of IEEE 802.11 has lower performance in heavy contention environment. Based on the in-depth analysis of IEEE 802.11 DCF, NSAD (Ne...Previous researches have shown that Distributed Coordination Function (DCF) access mode of IEEE 802.11 has lower performance in heavy contention environment. Based on the in-depth analysis of IEEE 802.11 DCF, NSAD (New Self-adapt DCF-based protocol) has been proposed to improve system saturation-throughput in heavy contention condition. The initial contention window tuning algorithm of NSAD is proved effective in error-free environment. However, problems concerning the exchanging of initial contention window occur in error-prone environment. Based on the analysis of NSAD's performance in error-prone environment, RSAD is proposed to further enhance the performance. Simulation in a more real shadowing error-prone environment is done to compare the performance of NSAD and RSAD and results have shown that RSAD can achieve further performance improvement as expected in the-error-prone environment than NSAD (i.e., better goodput and fairness index).展开更多
This paper researches the sniff technology of 802. 11b wireless LAN. It describes the channel, topology,authentication and privacy of WLAN, points out the way to capture wireless data, then presents the analyse proce-...This paper researches the sniff technology of 802. 11b wireless LAN. It describes the channel, topology,authentication and privacy of WLAN, points out the way to capture wireless data, then presents the analyse proce-dure of wireless frames. At last an actual frame is given.展开更多
文摘Previous researches have shown that Distributed Coordination Function (DCF) access mode of IEEE 802.11 has lower performance in heavy contention environment. Based on the in-depth analysis of IEEE 802.11 DCF, NSAD (New Self-adapt DCF-based protocol) has been proposed to improve system saturation-throughput in heavy contention condition. The initial contention window tuning algorithm of NSAD is proved effective in error-free environment. However, problems concerning the exchanging of initial contention window occur in error-prone environment. Based on the analysis of NSAD's performance in error-prone environment, RSAD is proposed to further enhance the performance. Simulation in a more real shadowing error-prone environment is done to compare the performance of NSAD and RSAD and results have shown that RSAD can achieve further performance improvement as expected in the-error-prone environment than NSAD (i.e., better goodput and fairness index).
文摘This paper researches the sniff technology of 802. 11b wireless LAN. It describes the channel, topology,authentication and privacy of WLAN, points out the way to capture wireless data, then presents the analyse proce-dure of wireless frames. At last an actual frame is given.