Cryptology ePrint Archive: Report 2009/630

Information-Theoretically Secure Protocols and Security Under Composition

Eyal Kushilevitz and Yehuda Lindell and Tal Rabin

Abstract: We investigate the question of whether security of protocols in the information-theoretic setting (where the adversary is computationally unbounded) implies the security of these protocols under concurrent composition. This question is motivated by the folklore that all known protocols that are secure in the information-theoretic setting are indeed secure under concurrent composition. We provide answers to this question for a number of different settings (i.e., considering perfect versus statistical security, and concurrent composition with adaptive versus fixed inputs). Our results enhance the understanding of what is necessary for obtaining security under composition, as well as providing tools (i.e., composition theorems) that can be used for proving the security of protocols under composition while considering only the standard stand-alone definitions of security.

Category / Keywords: cryptographic protocols / secure multiparty computation, information-theoretic security, security under composition

Publication Info: An extended abstract of this paper appeared in STOC 2006. This is the full version.

Date: received 20 Dec 2009

Contact author: lindell at cs biu ac il

Available format(s): PDF | BibTeX Citation

Version: 20091226:164656 (All versions of this report)

Short URL: ia.cr/2009/630

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