This is the first component of the hardware system layer. The network module is the east-west and north-south communication module. The network layer is cognizant of the fog topology and routing. It has the role of routing physically to other nodes. This is a major difference from a traditional cloud network that virtualizes all internal interfaces. Here the network has meaning and geographical presence in an IoT deployment. For example, a parent node hosting four other child nodes all attached to cameras may have the responsibility of aggregating video data from the four sources and sticking (fusing) the image content together to create a 360° field of view. To do this, it must know which child node pertains to which direction, and it cannot do that arbitrarily or randomly. 

The network component requirements include:

• Resilient, in case a communication link goes down. In effect, it may need to understand how to rebuild a mesh to keep data flowing.
• The network layer is also the place for data translation and re-packaging from non-IP sensors to IP protocols. Examples of this are Bluetooth, Z-Wave, and wired sensors.
• Handling failover cases.
• Binding to a variety of communication fabrics (Wi-Fi, wired, 5G).
• Providing the typical network infrastructure needed for an enterprise deployment (security, routing, and so on).