Committed Oblivious Transfer and Private Multi-Party Computation

Abstract. In this paper we present an eficient protocol for “Committed Oblivious Transfer” to perform oblivious transfer on committed bits: suppose Alice is committed to bits 00 and a1 and Bob is committed to b, they both want Bob to learn and commit to Ob without Alice learning b nor Bob learning ah. Our protocol, based on the properties of error correcting codes, uses Bit Commitment (BC) and one-out-of-two Oblivious Transfer (OT) as black boxes. Consequently the protocol may be implemented with or without a computational assumption, depending on the kind of BC and OT used by the participants. Assuming a Broadcast Channel is also available, we exploit this result to obtain a protocol for Private Multi-Party Computation, without making assumptions about a specific number or fraction of participants being honest. We analyze the protocol’s efficiency in terms of BCs and OTS performed. Our approach connects Zero Knowledge proofs on BCS, Oblivious Circuit Evaluation and Private Multi...

• Type: Conference
• Year: 1995
• Where: CRYPTO
• Authors: Claude Crépeau, Jeroen van de Graaf, Alain Tapp
• Keywords: Committed Oblivious Transfer, CRYPTO 1995, Cryptology, Oblivious Transfer, Private Multi-party Computations