@misc{cryptoeprint:2008:074,
author = {Bae Eun Jung and Hee Jean Kim},
title = {On the Chikazawa-Inoue ID based key system},
howpublished = {Cryptology ePrint Archive, Report 2008/074},
year = {2008},
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.