I was recently elected chair of the Security Marketing task group at the Wi-Fi Alliance, and one of the projects we are working on could benefit from data on the deployment of different types of security.
That is, what fraction of wireless networks are open/WEP/WPA/WPA2?
In the past, the task group used the RSA Wireless Security Survey, which was produced annually from 2001 through 2008 (the 2007 & 2008 surveys are available here). The RSA survey produced data for London, Paris, and New York; from the survey, it was clear what fraction of networks were open, had the horrible protection of WEP, or the more serious protection of WPA.
RSA’s data is the best we’ve found, but it doesn’t appear to have been produced since 2008. If anybody knows of a better source of data since then, please drop a comment below or emailme directly at email@example.com.