@misc{cryptoeprint:2008:276,
author = {Chandrasekar S. and Ambika K. and Pandu Rangan C.},
title = {Signcryption with Proxy Re-encryption},
howpublished = {Cryptology ePrint Archive, Report 2008/276},
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.