Towards Fine-Grained Access Control in Enterprise-Scale Internet-of-Things

Scalable, fine-grained access control for Internet-of-Things is needed in enterprise environments, where tens of thousands of users need to access smart objects which have a similar or larger order of magnitude. Existing solutions offer all-or-nothing access, or require all access to go through a cloud backend, greatly impeding access granularity, robustness and scale. In this paper, we propose Heracles, an IoT access control system which achieves robust, fine-grained access control and responsive execution at enterprise scale. Heracles adopts a capability-based approach using secure, unforgeable tokens that describe the authorizations of users, to either individuals or collections of objects in single or bulk operations. It has a 3-tier architecture to provide centralized policy and distributed execution desired in enterprise environments. Extensive analysis and performance evaluation on a testbed prove that Heracles achieves fine-grained access control and responsive execution at enterprise scale. Compared with systems using access control list, Heracles eliminates or reduces by 10x-100x the updating overhead under frequent changes of subject memberships and policies. Besides, Heracles achieves responsive execution: it takes 0.57 second to access 18 objects which are scattered 1-9 hops away, and execution on a 1-hop or 2-hop object needs only 0.07 or 0.13 second respectively.