On the notion of statistical security in simulatability definitions

Authors:
Dennis Hofheinz;Dominique Unruh
Affiliations:
IAKS, Arbeitsgruppe Systemsicherheit, Prof. Dr. Th. Beth, Fakultät für Informatik, Universität Karlsruhe, Germany;IAKS, Arbeitsgruppe Systemsicherheit, Prof. Dr. Th. Beth, Fakultät für Informatik, Universität Karlsruhe, Germany
Venue:
ISC'05 Proceedings of the 8th international conference on Information Security
Year:
2005

Citing 5
Cited 1

On the Composition of Zero-Knowledge Proof Systems

ICALP '90 Proceedings of the 17th International Colloquium on Automata, Languages and Programming
Universally Composable Security: A New Paradigm for Cryptographic Protocols

FOCS '01 Proceedings of the 42nd IEEE symposium on Foundations of Computer Science
A Model for Asynchronous Reactive Systems and its Application to Secure Message Transmission

SP '01 Proceedings of the 2001 IEEE Symposium on Security and Privacy
On the limitations of universally composable two-party computation without set-up assumptions

EUROCRYPT'03 Proceedings of the 22nd international conference on Theory and applications of cryptographic techniques
Comparing two notions of simulatability

TCC'05 Proceedings of the Second international conference on Theory of Cryptography

The reactive simulatability (RSIM) framework for asynchronous systems

Information and Computation

Quantified Score

Hi-index	0.00

Visualization

Abstract

We investigate the definition of statistical security (i.e., security against unbounded adversaries) in the framework of reactive simulatability. This framework allows to formulate and analyze multi-party protocols modularly by providing a composition theorem for protocols. However, we show that the notion of statistical security, as defined by Backes, Pfitzmann and Waidner for the reactive simulatability framework, does not allow for secure composition of protocols. This in particular invalidates the proof of the composition theorem. We give evidence that the reason for the non-composability of statistical security is no artifact of the framework itself, but of the particular formulation of statistical security. Therefore, we give a modified notion of statistical security in the reactive simulatability framework. We prove that this notion allows for secure composition of protocols. As to the best of our knowledge, no formal definition of statistical security has been fixed for Canetti's universal composability framework, we believe that our observations and results can also help to avoid potential pitfalls there.