Do we all really know what a fog node is? Current trends towards an open definition

Abstract

Abstract:Fog computing has emerged as a promising technology that can bring cloud applications closer to the physical IoT devices at the network edge. While it is widely known what cloud computing is, how data centers can build the cloud infrastructure and how applications can make use of this infrastructure, there is no common picture on what fog computing and particularly a fog node, as its main building block, really is. One of the first attempts to define a fog node was made by Cisco, qualifying a fog computing system as a "mini-cloud" located at the edge of the network and implemented through a variety of edge devices, interconnected by a variety, mostly wireless, communication technologies. Thus, a fog node would be the infrastructure implementing the said mini-cloud. Other proposals have their own definition of what a fog node is, usually in relation to a specific edge device, a specific use case or an application. In this paper, we first survey the state of the art in technologies for fog computing nodes, paying special attention to the contributions that analyze the role edge devices play in the fog node definition. We summarize and compare the concepts, lessons learned from their implementation, and end up showing how a conceptual framework is emerging towards a unifying fog node definition. We focus on core functionalities of a fog node as well as in the accompanying opportunities and challenges towards their practical realization in the near future.

All one needs to know about fog computing and related edge computing paradigms: A complete survey

“…The very definition of fog computing and fog nodes is a topic of ongoing discussion, and there is no common consensus on what a fog node is [70]. There are some early efforts to define fog and fog nodes [6,70]. OpenFog Consortium is one of the pioneers in standardizing and defining fog computing.…”

Quality of service‐aware approaches in fog computing

“…In other words, fog nodes can operate independently and communicate with other nodes, if required, or can be federated in a cluster. For executing FC capabilities, fog nodes need to support one or some of the following features 28,29 :…”

“…In other words, fog nodes can operate independently and communicate with other nodes, if required, or can be federated in a cluster. For executing FC capabilities, fog nodes need to support one or some of the following features: The capability of operating independently and with the local decision at node level or the node cluster level. The existence of different factors and the capability of development in diverse and extended environments. The capability of supporting hierarchical structure with different layers to create different collections of service functions. The capability of management and orchestrating by complicated systems to operate automatically. The programmable capability in different levels by some stakeholders such as end users, network operators, or equipment providers. …”

Fog orchestration for the Internet of Everything: state-of-the-art and research challenges

“…The resource discovery is a process where different computational capacities (e.g. CPU memory, storage) can be reported to the management unit so it can account for the resources available in the overall system [56]. This process also refers to the associations of devices grouped, known as Cloudlets, that embody the Fog.…”