Universally composable multi-party computation using tamper-proof hardware

Protocols proven secure within the universal composability (UC) framework satisfy strong and desirable security properties. Unfortunately, it is known that within the “plain” model, secure computation of general functionalities without an honest majority is impossible. This has prompted researchers to propose various “setup assumptions” with which to augment the bare UC framework in order to bypass this severe negative result. Existing setup assumptions seem to inherently require some trusted party (or parties) to initialize the setup in the real world.We propose a new setup assumption — more along the lines of a physical assumption regarding the existence of tamper-proof hardware — which also suffices to circumvent the impossibility result mentioned above. We suggest this assumption as potentially leading to an approach that might alleviate the need for trusted parties, and compare our assumption to those proposed previously.