Efficient and Universally Composable Committed Oblivious Transfer and Applications Academic Article uri icon


  • Committed Oblivious Transfer (COT) is a useful cryptographic primitive that combines the functionalities of bit commitment and oblivious transfer. In this paper, we introduce an extended version of COT (ECOT) which additionally allows proofs of relations among committed bits, and we construct an efficient protocol that securely realizes an ECOT functionality in the universal-composability (UC) framework. Our construction is more efficient than previous (non-UC) constructions of COT, involving only a constant number of exponentiations and communication rounds. Using the ECOT functionality as a building block, we construct efficient UC protocols for general two-party and multi-party functionalities, each gate requiring a constant number of ECOT's. Springer-Verlag 2004.

published proceedings

  • Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

author list (cited authors)

  • Garay, J. A., MacKenzie, P., & Yang, K.

complete list of authors

  • Garay, JA||MacKenzie, P||Yang, K

publication date

  • December 2004