Optimization of Garbled Circuit Construction to Enhance Efficiency of Secure Computation Protocols

Abstract

Secure Computation is an emerging part of Cryptography that is used for computing on newlineprivate data of repudiation parties through insecure channels, without the involvement of newlinea trusted third party. Traditional cryptography requires the availability of data to carry out encryptions, whereas in many applications sensitive data cannot be made available for processing. To handle these situations, we require secure computation. Depending on the various characteristics of secure computation protocols, different settings are available, newlinebased on that different protocols are developed. The main components of any secure newlinecomputation protocol design are Garbled Circuit construction and Oblivious Transfers. newlineGarbled circuit construction is the process of representing any mathematical functionality in encoded circuit form with correctness, privacy, obliviousness, and authenticity. Oblivious transfers help in the transfer of information by the sender in an oblivious manner. Construction of garbled circuits is a much more complex operation that again increases with the circuit size, which is directly proportional to the complexity of the application, newlinemaking secure computation applications theoretical. Hence, optimization of garbled circuit construction is required to improve the practicality of secure computation protocols. Various optimizations are tried in literature to improve the computation and communication complexity of garbled circuit construction. In this thesis, two major optimizations are developed where they could achieve 35 %, and 67 % of reduction in computation complexity, as well as 33 % of reduction in communication complexity for garbled circuit construction, without compromising the security of protocols. The identified optimizations can be applied to blockchain networks to develop blockchain applications with privacy, and efficiency improved with cloud computing. Accordingly, two frameworks FGUGChain, and CaFGUGChain are proposed to be worked on blockchain, and that newlinecould be extended to cloud computing... newline