@inproceedings{d2f435b01d974a75bf54bbca67720def,
title = "Unbounded hierarchical identity-based encryption with efficient revocation",
abstract = "Hierarchical identity-based encryption (HIBE) is an extension of identity-based encryption (IBE) where an identity of a user is organized as a hierarchical structure and a user can delegate the private key generation to another user. Providing a revocation mechanism for HIBE is highly necessary to keep a system securely. Revocable HIBE (RHIBE) is an HIBE scheme that can revoke a user{\textquoteright}s private key if his credential is expired or revealed. In this paper, we first propose an unbounded HIBE scheme where the maximum hierarchy depth is not limited and prove its selective security under a q-type assumption. Next, we propose an efficient unbounded RHIBE scheme by combining our unbounded HIBE scheme and a binary tree structure, and then we prove its selective security. By presenting the unbounded RHIBE scheme, we solve the open problem of Seo and Emura in CT-RSA 2015.",
keywords = "Bilinear maps, Hierarchical identity-based encryption, Identity-based encryption, Revocation, Unbounded hierarchy depth",
author = "Geumsook Ryu and Kwangsu Lee and Seunghwan Park and Lee, {Dong Hoon}",
note = "Funding Information: This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. 2010-0029121). The first two authors (Geumsook Ryu and Kwangsu Lee) equally contributed to this work. Publisher Copyright: {\textcopyright} Springer International Publishing Switzerland 2016.; 16th International Workshop on Information Security Applications, WISA 2015 ; Conference date: 20-08-2015 Through 22-08-2015",
year = "2016",
doi = "10.1007/978-3-319-31875-2_11",
language = "English",
isbn = "9783319318745",
series = "Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)",
publisher = "Springer Verlag",
pages = "122--133",
editor = "Dooho Choi and Ho-Won Kim",
booktitle = "Information Security Applications - 16th International Workshop, WISA 2015, Revised Selected Papers",
}