Efficient Adaptive Oblivious Transfer Without q-type Assumptions in UC Framework

Abstract

Oblivious transfer is one of the basic building blocks of cryptography. Due to its importance as a building block in the construction of secure multiparty computation protocols, the efficiency and security are two big issues in its design. In this paper, we present an efficient, universal composable (UC) secure adaptive oblivious transfer without qtype assumptions. The proposed protocol is UC secure under Decision Linear (DLIN), Decision Bilinear Diffie-Hellman (DBDH) and Square Decision Bilinear Diffie-Hellman (SqDBDH) assumptions in the presence of malicious adversary in static corruption model. The proposed protocol exhibits low computation and communication overheads as compared to the existing similar schemes.

Symmetric Blind Decryption with Perfect Secrecy

“…There are other suggestions for oblivious transfer based on problems in bilinear groups [30], groups of composite order [31], and the Diffie-Hellman problem [32][33][34][35][36][37]. These schemes are based on computational assumptions.…”

“…Camenisch, Neven and Shelat extended the work of Naor and Pinkas by defining simulatable oblivious transfer [29] and providing practical constructions for such a scheme. There are other suggestions for oblivious transfer based on problems in bilinear groups [30], groups of composite order [31] and the Diffie-Hellman problem [32]- [37]. These schemes are based on computational assumptions.…”