@misc{cryptoeprint:2010:371,
author = {Nicolas Estibals},
title = {Compact hardware for computing the Tate pairing over 128-bit-security supersingular curves},
howpublished = {Cryptology ePrint Archive, Report 2010/371},
year = {2010},
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.