We show that computational standard simulatability does not allow for secure concurrent composition of polynomially many protocols, but we also show that statistical standard simulatability does. The first result assumes the existence of an interesting cryptographic tool (namely time-lock puzzles), and its proof employs a cryptographic multi-party computation in an interesting and unconventional way.
Category / Keywords: cryptographic protocols / Reactive Simulatability, Universal Composability, concurrent composition Publication Info: Short version accepted at IEEE SSP 2006. This is the full version. Date: received 31 Mar 2006 Contact author: Dennis Hofheinz at cwi nl Available format(s): Postscript (PS) | Compressed Postscript (PS.GZ) | BibTeX Citation Version: 20060403:153352 (All versions of this report) Short URL: ia.cr/2006/130 Discussion forum: Show discussion | Start new discussion