What are the rules for arranging nodes in a network?

A network topology can be arranged into any shape with respect to the following rules:

• A node is one of an area node, edge node or instance node.
• Each node can only be the child of one parent node at most.
• An instance node can only be the child of an edge node.
• An edge node can only be the child of an area node.
• An area node can only be the child of another area node.