On-the-Fly Multiparty Computation on the Cloud via Multikey Fully Homomorphic Encryption
The authors propose a new notion of secure multiparty computation aided by a computationally powerful but untrusted \"Cloud\" server. In this notion that they call on-the-fly Multi-Party Computation (MPC), the cloud can non-interactively perform arbitrary, dynamically chosen computations on data belonging to arbitrary sets of users chosen on-the-fly. All user's input data and intermediate results are protected from snooping by the cloud as well as other users. This extends the standard notion of Fully Homomorphic Encryption (FHE), where users can only enlist the cloud's help in evaluating functions on their own encrypted data.