The acute need of the multitude of smart, end-user IoT devices and near-user edge devices to carry out, with minimal latency, a substantial amount of data processing and to collaborate in a distributed way, triggered technology advancements towards adaptive, decentralized computational paradigms that complement the centralized cloud computing model serving IoT networks.
Researchers, computer scientists, system and network engineers developed innovative solutions to fill the technological gaps. These solutions provide faster approaches that gain better situational awareness in a far more timely manner. Such solutions or computational paradigms are referred to as fog computing, mist computing, cloudlets4, or edge computing5,6. Since no consensus exists on distinction among these concepts at the time this document was created, the authors considered it imperative to provide a conceptual model that can be used by practitioners and researchers to facilitate meaningful conversations on the topic.
This document provides the conceptual model of fog computing and its subsidiary mist computing, and aims to place these concepts in relation to cloud computing7 and edge computing.
Additionally, the document introduces the notion of a fog node and the nodes federation model composed of both, distributed and centralized, often hierarhical clusters of fog nodes operating in harmony. This model is introduced as a building-block architectural approach for constructing, enhancing or expanding the fog and mist computing layers.
Furthermore, the document characterizes important aspects of fog computing and is intended to serve as a means for broad comparisons of fog computing capabilities, service models and deployment strategies, and to provide a baseline for discussion of what fog computing is and the way it may be used.
The capabilities, service types and deployment models form a simple taxonomy that is not intended to prescribe or constrain any particular method of deployment, service delivery, or business operation.