Visible to the public New Notions of Security: Achieving Universal Composability Without Trusted Setup

TitleNew Notions of Security: Achieving Universal Composability Without Trusted Setup
Publication TypeConference Paper
Year of Publication2004
AuthorsPrabhakaran, Manoj, Sahai, Amit
Conference NameProceedings of the Thirty-sixth Annual ACM Symposium on Theory of Computing
Date PublishedJune 2004
Conference LocationNew York, NY, USA
ISBN Number978-1-58113-852-8
Keywordscomposability, compositionality, environmental security, general composition, generalized environmental security, pubcrawl, secure multi-party computation, secure protocols, simulation, universal composability

We propose a modification to the framework of Universally Composable (UC) security [3]. Our new notion involves comparing the real protocol execution with an ideal execution involving ideal functionalities (just as in UC-security), but allowing the environment and adversary access to some super-polynomial computational power. We argue the meaningfulness of the new notion, which in particular subsumes many of the traditional notions of security. We generalize the Universal Composition theorem of [3] to the new setting. Then under new computational assumptions, we realize secure multi-party computation (for static adversaries) without a common reference string or any other set-up assumptions, in the new framework. This is known to be impossible under the UC framework.

Citation Keyprabhakaran_new_2004