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Wifi-Reports: Improving Wireless Network Selection with Collaboration
December 2010 (vol. 9 no. 12)
pp. 1713-1731
Jeffrey Pang, Carnegie Mellon University, Pittsburgh
Ben Greenstein, Intel Labs, Seattle
Michael Kaminsky, Intel Labs, Pittsburgh
Damon McCoy, University of California, San Diego
Srinivasan Seshan, Carnegie Mellon University, Pittsburgh
Wi-Fi clients can obtain much better performance at some commercial hot spots than others. Unfortunately, there is currently no way for users to determine which hot spot access points (APs) will be sufficient to run their applications before purchasing access. To address this problem, this paper presents Wifi-Reports, a collaborative service that provides Wi-Fi clients with historical information about AP performance and application support. The key research challenge in Wifi-Reports is to obtain accurate user-submitted reports. This is challenging because two conflicting goals must be addressed in a practical system: preserving the privacy of users' reports and limiting fraudulent reports. We introduce a practical cryptographic protocol that achieves both goals, and address the important engineering challenges in building Wifi-Reports. Using a measurement study of APs in a busy commercial district, we show that Wifi-Reports would improve the performance over previous AP selection approaches in 30-60 percent of locations.

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Index Terms:
Privacy, anonymity, wireless, reputation, 802.11.
Jeffrey Pang, Ben Greenstein, Michael Kaminsky, Damon McCoy, Srinivasan Seshan, "Wifi-Reports: Improving Wireless Network Selection with Collaboration," IEEE Transactions on Mobile Computing, vol. 9, no. 12, pp. 1713-1731, Dec. 2010, doi:10.1109/TMC.2010.151
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