@misc{cryptoeprint:2005:280,
author = {D. Page},
title = {Partitioned Cache Architecture as a Side-Channel Defence Mechanism},
howpublished = {Cryptology ePrint Archive, Report 2005/280},
year = {2005},
note = {\url{http://eprint.iacr.org/}},
}
You will need the url.sty package (comes with most LaTeX installations) for the last line. Otherwise, remove the \url command.