Edge, cloud and fog computing are types of distributed computing that respectively delineate the physical deployment of compute and storage resources in relation to various edge locations, or where the data is produced. The difference between the three lies in where the resources are located.
For edge computing, organizations deploy computing and storage resources where the data is produced (for example, edge servers and storage installed on a wind turbine to collect and process data that’s produced by sensors inside.)
In the case of cloud computing, compute and storage resources are deployed at several distributed areas. The closest cloud facilities tend to be hundreds of miles away from the site of data collection, and the connection quality is dependent on internet connectivity.
Fog computing offers a third option when cloud data centers are too far away and when the edge deployment resources are limited or too scattered to be a viable solution. When the sensor and IoT datasets are too large to count as “edge,” fog computing puts compute and storage “within” the data. Smart cities are a good example of fog computing environments, as they generate too much data for a single edge deployment to handle. Instead, they rely on fog node deployments for collecting, processing and analyzing data within the environment. Some use the terms “fog computing” and “edge computing” synonymously, but the two operate at different scales.