Countries with the most botnets

[smb at cs.columbia.edu (Steven Bellovin)]

A colleague needs to know, along with citable sources if possible.

Ideally - number of zombified PCs, percentage of zombified PCs, name of
nation, source.

Threat reports from symantec and macafee suggest the US leads, with
China a very close second.

Yes, we realize that answers will be imperfect.

		--Steve Bellovin, http://www.cs.columbia.edu/~smb