Time-Based Access Control for Multi-attribute Data in Internet of Things

Internet of Things (IoT) has become a vital part of our infrastructure to enrich lives and make processes easier. In these people-centric IoT applications, massive personal data are collected in real-time and stored by the resource constrained sensor network. Because any misusage of these personal data might result in the leakage of privacy and economic losses, it is expected that the data requesters can only access to the data what they have purchased, or are entitled to use. How to accurately control data access permissions is one of the prerequisites for IoT data protection. Based on a revised one-way hash chain technique, we proposed a novel Time-based Access Control (TAC) scheme for multi-attribute data in Internet of Things. All the data are partitioned into 2-D subspaces representing generation time and data attribute. Data in each subspace is encrypted with the corresponding sub-key before its transmission to the base station to achieve data privacy and access control. Anyone who wants to read or use data with specified attribute at a particular time must get the corresponding sub-key from the data source node or the owner. TAC can generate a sub-key for data in each subspace in an efficient manner in terms of less sub-key generation time and low memory space usage. We proposed three improved schemes to further reduce sub-key computation time according to different application scenarios. The experimental results show that TAC can be applied to the resource limited WSNs efficiently.