Cryptology ePrint Archive: Report 2013/115
A Conditional Proxy Broadcast Re-Encryption Scheme Supporting Timed-Release
Kaitai Liang and Qiong Huang and Roman Schlegel and Duncan S. Wong and Chunming Tang
Abstract: To allow a delegator not only to delegate the keyword-controlled
decryption rights of a broadcast encryption to a set of specified recipi-
ents, but also to control when the decryption rights will be delegated, in this paper, for the first time, we introduce a new notion called Timed-
Release Conditional Proxy Broadcast Re-Encryption (TR-CPBRE). We
also propose a concrete construction for TR-CPBRE which can be proven
selective identity adaptive CCA secure under the (P; Q; f)-general de-
cisional Diffie-Hellman exponent assumption, and chosen-time period
chosen-ciphertext secure under the bilinear Diffie-Hellman assumption.
When compared with the existing CPBRE and Timed-Release Proxy
Re-Encryption (TR-PRE) schemes, our scheme achieves better efficiency,
and enables the delegator to make a fine-grained delegation of decryption
rights to multiple delegatees.
Category / Keywords: timed-release encryption, unidirectional conditional proxy broadcast re-encryption, bilinear map.
Date: received 27 Feb 2013, last revised 5 May 2013
Contact author: kliang4-c at my cityu edu hk
Available format(s): PDF | BibTeX Citation
Version: 20190217:224314 (All versions of this report)
Short URL: ia.cr/2013/115
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