Paper 2013/115

A Conditional Proxy Broadcast Re-Encryption Scheme Supporting Timed-Release

Kaitai Liang, Qiong Huang, Roman Schlegel, Duncan S. Wong, and Chunming Tang


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.

Available format(s)
Publication info
Published elsewhere. Unknown where it was published
timed-release encryptionbilinear map.
Contact author(s)
kliang4-c @ my cityu edu hk
2013-05-06: last of 4 revisions
2013-02-27: received
See all versions
Short URL
Creative Commons Attribution


      author = {Kaitai Liang and Qiong Huang and Roman Schlegel and Duncan S.  Wong and Chunming Tang},
      title = {A Conditional Proxy Broadcast Re-Encryption Scheme Supporting Timed-Release},
      howpublished = {Cryptology ePrint Archive, Paper 2013/115},
      year = {2013},
      note = {\url{}},
      url = {}
Note: In order to protect the privacy of readers, does not use cookies or embedded third party content.