The protocol abstraction layer binds the lowest elements of the IoT system (sensors) with other layers of the fog node, other fog nodes, and the cloud. OpenFog advocates an abstraction model to identify and communicate with a sensor device through the protocol abstraction layer. By abstracting the interface to sensors and edge devices, a heterogeneous mixture of sensors can be deployed on a single fog node, for example, analog devices that pass through digital-to-analog converters as well as digital sensors. Even the interfaces to the sensors can be individualized, such as Bluetooth to temperature devices in vehicles, can bus to other engine sensors, SPI interfaced sensors on various vehicle electronics, and GPIO sensors to the various door and theft sensors. By abstracting the interface, the upper-layers of the software stack can access such disparate devices through a standardized approach.