Fog computing is a distributed computing architecture, as opposed to depending entirely on centralized cloud servers, which brings the processing of data, functionality of an application, and its storage closer to the network's edge, where it can be closer to the data source or an end‐user device. Some of the potential applications of the fog computing‐based Internet of Things (IoT)‐enabled system are smart healthcare, smart agriculture, smart manufacturing, intelligent transportation system, and smart cities (i.e., in parking management, lighting control, traffic control, and security of civilians). The fog computing‐based IoT‐enabled system is vulnerable to various attacks. Therefore, one needs to deploy security mechanisms, like authentication, access control, key management, and malware detection, in order to secure its communication. In this article, we design a signature‐based access control and key management scheme for fog computing‐based IoT‐enabled big data applications (in short, SBAC‐FC). A detailed security analysis and performance comparison of the SBAC‐FC with other similar existing schemes reveal that the SBAC‐FC surpasses the existing schemes in terms of security and functionality characteristics, as well as complexity overheads.