Definition of fog computing.
According to Atlam et al., (2018), fog computing is a model that has defined capabilities such as computing, storing and networking services (Atlam et al., 2018), between cloud data centres and end devices. Due to the large growth of connected devices fog computing extends cloud computing model, by ensuring that all its resources are placed at the edge of the network. Since the devices such as the wireless gateways, sensors and actuators lack in terms of capacity, fog computing brings computing power, storage and memory capacity closer (Santos et al., 2017). According to Patil, (2017) this model allows applications on billions of connected devices, already connected on the IoT (Internet of Things) to run directly at the network edge.
Figure 1. Fog computing broadening of cloud computing.
(Atlam et al., 2018)
From the definition above and based of Figure 1, we could fundamentally say fog computing is the broadening of cloud computing but it is close to things that always work with IoT. As shown in Figure 1, fog computing acts a mediator (middle layer) between cloud and end devices, it acts as a mediator that brings processing, storage, and network services closer to the end devices.
Characteristics of Fog Computing.
According to Atlam et al.,(2018) and Patil, (2017) Fog Computing characteristics include the following:
1. Low latency and Location awareness: having the fog closer to the end devices, provides low latency when processing the data of the end devices, and thus support location awareness in manner that allows for nodes to be deployed anywhere in different locations.
2. Wide spread geographical distribution: the application and services can be deployed anywhere.
3. Support for real time mobility access: fog computing enables mobility methods such as locator ID, because it has the ability to connect directly to mobile devices.
4. Strong presence of real time streaming and interaction: rather than batch processing in the cloud this models applications provide real time interaction between the fog nodes.
5. Seamless Interoperability: provides better communication between devices from different vendors and across various domains.