Cryptology ePrint Archive: Report 2006/473

Identity-Based Proxy Re-encryption

Matthew Green and Giuseppe Ateniese

Abstract: In a proxy re-encryption scheme a semi-trusted proxy converts a ciphertext for Alice into a ciphertext for Bob {\em without} seeing the underlying plaintext. A number of solutions have been proposed in the public-key setting. In this paper, we address the problem of Identity-Based proxy re-encryption, where ciphertexts are transformed from one {\it identity} to another. Our schemes are compatible with current IBE deployments and do not require any extra work from the IBE trusted-party key generator. In addition, they are non-interactive and one of them permits multiple re-encryptions. Their security is based on a standard assumption (DBDH) in the random oracle model.

Category / Keywords: public-key cryptography / proxy re-encryption, identity-based encryption, bilinear maps

Date: received 15 Dec 2006

Contact author: mgreen at cs jhu edu

Available formats: PDF | BibTeX Citation

Version: 20061216:130358 (All versions of this report)

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