Cryptology ePrint Archive: BibTeX Citation of Report 2012/490

@misc{cryptoeprint:2012:490,
    author = {Zahra Ahmadian, Mahmoud Salmasizadeh, and Mohammad Reza Aref},
    title = {Desynchronization Attack on RAPP Ultralightweight Authentication Protocol},
    howpublished = {Cryptology ePrint Archive, Report 2012/490},
    year = {2012},
    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.