In order to analyze a network consisting of nodes and chains, the following topology should be built.

Chain : Chain ID, Start Node ID, End Node ID, Attributes
Node: Node ID, (x, y), adjacent chain IDs (positive for to node, negative for from node)

In order to analyze not only a network but also relationships between polygons, the following addtional geometry and topology are required as shown in an example of Figure 2.3.

Chain geometry : Chain ID, Start Coordinates, Point Coordinates, End Coodinates
Polygon topology : Polygon ID, Series of Chain ID, in clockwise order (Attritutes)
Chain topology : Chain ID, Start Node ID, End Node ID, Left Polygon ID, Right Polygon ID, (Attributes)

The advantages of the topological data model are to avoid duplication in digitizing common boundaries of two polygons and to solve problems when the two versions of the common boundary do not coincide.

The disadvantages are to have to build very correct topological data sets without any single error and to be unable to represent islands in a polygon.