Commodity-based cryptography (extended abstract)
Donald Beaver · 1997
We introduce a new paradigm for the efficient de- sign of protocols for secure joint computation requiring minimal interaction.Instead of relying on trusted and specialized devices, unproven cryptographic assumptions, or highly interactive multiparty computations, we propose a commoditybased model in which servers provide security resources to clients but are not involved in the clients' computations themselves.Unlike oracles, which typically provide comput ational resources such as the resnlts of infeasible computations, these servers assist clients in establishing shared resources for secure computations such as oblivious transfer and circuit evaluation, broadcast and multiparty computations.Unlike protocols for secure multiparty computation, the servers themselves are "non-interactive," having no knowledge whatsoever of each other, and providing security resources in a single message.This approach to secure interactive computing obviates the need for unproven cryptographic assumptions, special hardware (such as oblivious transfer channels), completely-connected networks, or global knowledge and synchronization.It gracefully accommodates expansion without introducing bottlenecks (even polynomial) at larger scales.We give explicit constructions supporting oblivious transfer and network multicast.