Cryptology ePrint Archive: Report 2005/018

Collusion Resistant Broadcast Encryption With Short Ciphertexts and Private Keys

Dan Boneh and Craig Gentry and Brent Waters

Abstract: We describe two new public key broadcast encryption systems for stateless receivers. Both systems are fully secure against any number of colluders. In our first construction both ciphertexts and private keys are of constant size (only two group elements), for any subset of receivers. The public key size in this system is linear in the total number of receivers. Our second system is a generalization of the first that provides a tradeoff between ciphertext size and public key size. For example, we achieve a collusion resistant broadcast system for n users where both ciphertexts and public keys are of size O(sqrt(n)) for any subset of receivers. We discuss several applications of these systems.

Category / Keywords: public-key cryptography /

Date: received 27 Jan 2005, last revised 12 Mar 2005

Contact author: dabo at cs stanford edu

Available format(s): PDF | BibTeX Citation

Version: 20050312:224851 (All versions of this report)

Short URL: ia.cr/2005/018

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