Capability-Based Access Control Model for Fog Computing Model

Abstract

In the IoT (Internet of Things), sensor data is transmitted to servers in networks and processed by application processes on the servers. In the FC (Fog Computing) model of the IoT, fog nodes and device nodes have to be protected from malicious accesses. We take the CBAC (Capability-Based Access Control) model to control accesses to fog nodes and device nodes because it is sufficient for each node to check a capability token carried with an access request. As discussed in our previous studies, if data moves from a device node $d_i$ to another device node $d_j$ by some subject, even if subjects are not allowed to access to the data of the device node $d_i$, the subjects may get the data from the device node $d_j$, i.e. illegal information flow. Furthermore, a fog node generates a new output data by processing input data from other fog nodes. We newly propose a concept of component degree of each data transmitted among nodes, which shows how much sensor data is included in the data. Based on the component degree concept, we newly discuss information flow among fog nodes in the CBAC model.