@misc{cryptoeprint:2006:275,
author = {Debrup Chakraborty and Palash Sarkar},
title = {A New Mode of Encryption Providing A Tweakable Strong Pseudo-Random},
howpublished = {Cryptology ePrint Archive, Report 2006/275},
year = {2006},
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.