A survey on reliability and availability modeling of edge, fog, and cloud computing

During the past years, sending data to the cloud servers was a prominent trend, making the cloud computing paradigm dominate the technology landscape. However, the internet of things (IoT) is becoming a part of our daily environments, and it generates a large volume of data, which is creating uncontrollable delays. For the delay-sensitive and context-aware services, these uncontrollable delays may cause low reliability and availability for applications. To overcome these challenges, computing paradigms are moving from centralized cloud environments to the Edge of the networks. Several new computing paradigms, such as Edge and Fog computing, emerged to support delay-sensitive and context-aware services. By combining edge devices, fog servers, and cloud computing, companies can build a hierarchical IoT infrastructure, using Edge–Fog–Cloud orchestrated architecture to improve IoT environments’ performance, reliability, and availability. This paper presents a comprehensive survey on reliability and availability of Edge, Fog, and Cloud computing architectures. We first introduce and compare some related works about these paradigms and compare them to define the differences between Edge and Fog environments, since there is still some confusion about these terms. We also describe their taxonomy and how they link to each other. Finally, we draw some potential research directions that may help foster research efforts in this area.