Paper 2018/391
Tight Adaptively Secure Broadcast Encryption with Short Ciphertexts and Keys
Romain Gay, Lucas Kowalczyk, and Hoeteck Wee
Abstract
We present a new public key broadcast encryption scheme where both the ciphertext and secret keys consist of a constant number of group elements. Our result improves upon the work of Boneh, Gentry, and Waters (Crypto '05) as well as several recent follow-ups (TCC '16-A, Asiacrypt '16) in two ways: (i) we achieve adaptive security instead of selective security, and (ii) our construction relies on the decisional $k$-Linear Assumption in prime-order groups (as opposed to $q$-type assumptions or subgroup decisional assumptions in composite-order groups); our improvements come at the cost of a larger public key. Finally, we show that our scheme achieves adaptive security in the multi-ciphertext setting with a security loss that is independent of the number of challenge ciphertexts.
Metadata
- Available format(s)
-
PDF
- Category
- Public-key cryptography
- Publication info
- Preprint. MINOR revision.
- Keywords
- broadcast encryptionbilinear group
- Contact author(s)
- luke @ cs columbia edu
- History
- 2018-05-01: received
- Short URL
- https://ia.cr/2018/391
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2018/391,
author = {Romain Gay and Lucas Kowalczyk and Hoeteck Wee},
title = {Tight Adaptively Secure Broadcast Encryption with Short Ciphertexts and Keys},
howpublished = {Cryptology {ePrint} Archive, Paper 2018/391},
year = {2018},
url = {https://eprint.iacr.org/2018/391}
}
