
A transport network can be represented by two object classes, defined as Link and Node, which are inherited. Because of the topological attributes of a network, a connection relationship has to be established between the link and node classes. It defines and nature and extent of the geometric connectivity supporting the network’s topology.
Object-oriented network models are stored in relational databases, such as a geodatabase. The above representation would require four relational tables; one labeled Transport Network, which could be a simple identifier for the network; a Node and a Link table containing their respective properties; and a Connection table where connectivity information is stored (which links connect which nodes).