Constant Ciphertext Length in CP-ABE

Nishant Doshi; Devesh Jinwala

Paper 2012/500

Constant Ciphertext Length in CP-ABE

Nishant Doshi and Devesh Jinwala

Abstract

Ciphertext policy attribute based encryption (CP-ABE) is a technique in which user with secret key containing attributes, only able to decrypt the message if the attributes in the policy match with the attributes in secret key. The existing methods that use reasonably computable decryption policies produce the ciphertext of size at least linearly varying with the number of attributes with additional pairing operations during encryption and decryption. In this paper, we propose a scheme in which ciphertext remains constant in length, irrespective of the number of attributes. Our scheme works for a threshold case: the number of attributes in a policy must be a subset of attributes in a secret key. The security of propose scheme is based on Decisional Bilinear Diffie-Hellman (DBDH) problem.

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: Published elsewhere. Unknown where it was published
Keywords: Attribute Attribute based encryption ciphertext policy constant ciphertext length
Contact author(s): doshinikki2004 @ gmail com
History: 2012-09-03: received
Short URL: https://ia.cr/2012/500
License: CC BY

BibTeX

@misc{cryptoeprint:2012/500,
      author = {Nishant Doshi and Devesh Jinwala},
      title = {Constant Ciphertext Length in {CP}-{ABE}},
      howpublished = {Cryptology {ePrint} Archive, Paper 2012/500},
      year = {2012},
      url = {https://eprint.iacr.org/2012/500}
}