Concurrent Composition of Secure Protocols in the Timing Model

In the setting of secure multiparty computation, a set of mutually distrustful parties wish to securely compute some joint function of their inputs. In the stand-alone case, it has been shown that every efficient function can be securely computed. However, in the setting of concurrent composition, broad impossibility results have been proven for the case of no honest majority and no trusted setup phase. These results hold both for the case of general composition (where a secure protocol is run many times concurrently with arbitrary other protocols) and self composition (where a single secure protocol is run many times concurrently). In this paper, we investigate the feasibility of obtaining security in the concurrent setting, assuming that each party has a local clock and that these clocks proceed at approximately the same rate. We show that under this mild timing assumption, it is possible to securely compute any multiparty functionality under concurrent self composition. Loosely spe...

• Type: Journal
• Year: 2007
• Where: JOC
• Authors: Yael Tauman Kalai, Yehuda Lindell, Manoj Prabhakaran
• Keywords: General Composition, JOC 2007, Secure Multiparty Computation, Secure Protocol