Task-Based Access Control for Computation and Communication in the Tactical Warfighting Edge

In the context of the Tactical Warfighting Edge (TWE) with dynamic interactions of edge devices and users, cyber attacks can disrupt computation and communication (C&C) tasks in a critical mission. Therefore, implementing a suitable Zero Trust (ZT) security architecture is necessary to: (a) enforce e.g., the law of least privilege, microsegmentation, and continuous authentication/access verification to limit attack impacts, and (b) secure TWE environments that are characterized as Denied, Disrupted, Intermittent, and Limited (DDIL) environments. Widely adopted methods in the enterprise settings such as Role-Based Access Control (RBAC) are unsuitable for the implementation of ZT in the TWE because they cause overprovisioning of privileges, and are not capable of handling DDIL resource constraints. In this paper, we present a novel ZT architecture viz., Arculus that utilizes Task-Based Access Control (TBAC) that secures C&C tasks in the TWE relating to a collaborative drone swarm (CDS) use case by dynamically assigning and revoking privileges in a just-in-time manner. We also detail how the Arculus-TBAC can handle DDIL constraints (e.g., limited battery, physical hijacking and network partition scenarios) via a sliding-scale ZT approach to ensure mission success in a situation-aware manner. Lastly, we implement our Arculus-TBAC approach using a realistic CDS testbed featuring a ‘stealthy reconnaissance and resupply mission’ in a TWE setting, and demonstrate the efficiency (i.e., without excessive privileges) and efficacy (i.e., ability to handle DDIL constraints) in securing C&C tasks of the mission.