Proceedings ArticleDOI
Proactive Scan: Fast Handoff with Smart Triggers for 802.11 Wireless LAN
Haitao Wu,Kun Tan,Yongguang Zhang,Qian Zhang +3 more
- pp 749-757
TLDR
It is shown that Proactive Scan does provide fast handoff and satisfactory performance to VoIP applications and is a software-only client-only solution that any mobile device can use in any existing 802.11 networks.Abstract:Â
It has been a challenging problem to support VoIP-type delay sensitive applications in an 802.11 wireless LAN, because the standard handoff procedure implemented in many current 802.11 products occurs a delay deem unacceptable to VoIP users. To reduce this delay, we have developed a fast handoff scheme called Proactive Scan. It employs two new techniques. The first is to decouple the time-consuming channel scan from the actual handoff, and to eliminate channel scan delay by doing scan early and interleaving it with ongoing traffic in a non-intrusive way. The second technique is a smart trigger that takes into account both uplink and downlink quality and explicitly addresses the link asymmetry which has yet not been touched in previous work. Through implementation and experimentation study, we have shown that Proactive Scan does provide fast handoff and satisfactory performance to VoIP applications. Further, it is a software-only client-only solution that any mobile device can use in any existing 802.11 networks.read more
Citations
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Supporting vehicular mobility in urban multi-hop wireless networks
TL;DR: This work designs and evaluates a family of client-driven handoff techniques that target vehicular mobility in multi-tier multi-hop wireless mesh networks and utilizes a 4,000 user urban deployment to evaluate the performance of a broad class of hand-off policies.
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User-level performance evaluation of VoIP using ns-2
TL;DR: In this paper, the authors present enhancements to the popular Network Simulator 2 (ns-2) that allow a reliable VoIP user-level performance analysis to be carried out through simulation.
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D-Scan: Enabling Fast and Smooth Handoffs in AP-Dense 802.11 Wireless Networks
TL;DR: This paper studies the handoff process in large AP-dense 802.11 networks, which is one of the most common forms of WiFi under usage, and develops a solution to significantly improve the essential process of AP scan, a bottleneck towards fast and smooth handoffs.
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