A Dynamic Time-Bound Access Control for Secure Hierarchical Content Sharing

Abstract

<p>With rapid growth of mobile users, protecting content from unauthorized users become a complex problem. The concept of temporal role-based access control reduces complexity of user management and restricts access to specified time-slots. But, content privacy is still questionable in case of system resources compromise unexpectedly. Therefore, cryptographic solution for time-bound hierarchical content management is an emerging problem. Most of the related schemes focused on individual user keys and/or revocation, but not on time-bound keys. Hence, these are not well suitable for subscription-based services like pay-TV and newspaper. In this paper, we propose a cryptographic time-bound access control with constant size time-bound keys. In our scheme, subscribed time-slots embed into individual user keys to avoid periodical broadcasting of temporal keys. We prove that our scheme is selectively secure against collision attack under chosen-ciphertext attack. We then discuss cloud-based application to show the strategies of efficient revocation and reduced computational overheads for end-users. </p>

ID-Based Deniable Authentication Protocol with Key Agreement and Time-Bound Properties for 6G-Based WBAN Healthcare Environments

“…Chien's protocol [19] uses two secure hash functions to acheive a time-bound security requirement. The system can randomly select two integers as x s and x e in GF(p), where p is a large prime.…”

“…Without this, login tickets could be exploited indefinitely, or lost devices might leave open sessions, potentially leading to unauthorized access or data breaches. A time-bound hierarchical key agreement thus restricts key derivation by class relationships and time, addressing these vulnerabilities [19].…”