What Does Overlay Network Mean?
An overlay network can be thought of as a computer network on top of another network. All nodes in an overlay network are connected with one another by means of logical or virtual links and each of these links correspond to a path in the underlying network.
Techopedia Explains Overlay Network
An example of an overlay network can be distributed systems such as client-server applications and peer-to-peer networks. Such applications or networks act as the overlay networks because all nodes in these applications and networks run on top of the internet.
