Enterprise Internet of Things Handbook

Which is better?

Fog computing pushes intelligence towards the smart devices, reducing the amount of data that needs to go to the cloud and decreasing operational latency between the user and the smart device. Cloud computing is a centralized system that can scale on demand and can perform on-demand analysis in real time, among other things.

Here is a table from Cisco's blog, written by Maher Abdelshkour, explaining the differences between cloud and fog computing:

Another table with a high-level comparison follows:

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