Time-based direct revocable Ciphertext-Policy Attribute-Based Encryption with short revocation list

Joseph K. Liu, Tsz Hon Yuen, Peng Zhang, Kaitai Liang

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearch

38 Citations (Scopus)


In this paper, we propose an efficient revocable Ciphertext-Policy Attribute-Based Encryption (CP-ABE) scheme. We base on the direct revocation approach, by embedding the revocation list into ciphertext. However, since the revocation list will grow longer as time goes by, we further leverage this by proposing a secret key time validation technique so that users will have their keys expired on a date and the revocation list only needs to include those user keys revoked before their intended expired date (e.g. those user keys which have been stolen before expiry). These keys can be removed from the revocation list after their expiry date in order to keep the revocation list short, as these keys can no longer be used to decrypt ciphertext generated after their expiry time. This technique is derived from Hierarchical Identity-based Encryption (HIBE) mechanism and thus time periods are in hierarchical structure: year, month, day. Users with validity of the whole year can decrypt any ciphertext associated with time period of any month or any day within the year. By using this technique, the size of public parameters and user secret key can be greatly reduced. A bonus advantage of this technique is the support of discontinuity of user validity (e.g. taking no-paid leave).

Original languageEnglish
Title of host publicationApplied Cryptography and Network Security
Subtitle of host publication16th International Conference, ACNS 2018 Leuven, Belgium, July 2–4, 2018 Proceedings
EditorsBart Preneel, Frederik Vercauteren
Place of PublicationCham Switzerland
Number of pages19
ISBN (Electronic)9783319933870
ISBN (Print)9783319933863
Publication statusPublished - 2018
EventInternational Conference on Applied Cryptography and Network Security 2018 - Leuven, Belgium
Duration: 2 Jul 20184 Jul 2018
Conference number: 16th
https://link.springer.com/book/10.1007/978-3-319-93387-0 (Proceedings)

Publication series

NameLecture Notes in Computer Science
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349


ConferenceInternational Conference on Applied Cryptography and Network Security 2018
Abbreviated titleACNS 2018
Internet address

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