Collusion-resistant Broadcast Encryption based on Hidden RSA Subgroups

Sigurd Eskeland

2022

Abstract

Public key broadcast encryption enables computations of ciphertexts, in which a single ciphertext is encrypted with regard to a set of recipients, and only the intended recipients can decrypt that ciphertext independently of each other and without interactions. A significant shortcoming of existing broadcast encryption schemes are long decryption keys comprising the public keys of pertaining recipients. Decryption therefore necessitates access to public keys, which requires key management and impacts computational and transmission overhead, accessibility, and storage. Moreover, a user description list referencing the pertaining recipients and their public keys must be appended to each ciphertext, which leads to the privacy implication of disclosing user/content-relations. Curiously, virtually all broadcast encryption schemes are based on bilinear pairings. In this paper, we propose a collusion-resistant broadcast encryption scheme that is the first broadcast encryption scheme based on the factorization problem and hidden RSA subgroups. A novel feature is that the decryption key consists of a single element only, which leads to significantly reduced key management, improved computational efficiency, and elimination of the mentioned privacy issue.

Paper Citation

in Harvard Style

Eskeland S. (2022). Collusion-resistant Broadcast Encryption based on Hidden RSA Subgroups. In Proceedings of the 19th International Conference on Security and Cryptography - Volume 1: SECRYPT, ISBN 978-989-758-590-6, pages 291-298. DOI: 10.5220/0011140000003283

in Bibtex Style

@conference{secrypt22,
author={Sigurd Eskeland},
title={Collusion-resistant Broadcast Encryption based on Hidden RSA Subgroups},
booktitle={Proceedings of the 19th International Conference on Security and Cryptography - Volume 1: SECRYPT,},
year={2022},
pages={291-298},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0011140000003283},
isbn={978-989-758-590-6},
}

in EndNote Style

TY - CONF

JO - Proceedings of the 19th International Conference on Security and Cryptography - Volume 1: SECRYPT,
TI - Collusion-resistant Broadcast Encryption based on Hidden RSA Subgroups
SN - 978-989-758-590-6
AU - Eskeland S.
PY - 2022
SP - 291
EP - 298
DO - 10.5220/0011140000003283