A fully connected mesh network is one in which every node has a direct connection to every other node in the network, as demonstrated in the following diagram:
If this diagram looks a bit crowded to you, you've already noticed the single biggest drawback of a fully-connected mesh network. It's nearly impossible to scale beyond a certain point, because each new node on the network requires a connection for each previously connected node on the network. The math works out to a quadratic increase in connections for each new node to be added. Moving past a few nodes on the network becomes physically impossible very ...
