In the DRM Database, road networks are depicted as combinations of "nodes" and "links" as illustrated in the figure right. A unique ID number is assigned to each node and each link.
| Node: | An intersection or other necessary nodal point of the roadway network. |
| Link: | A road segment between two nodes. |
Nodes and Links
Note: A link ID number consists of the ID numbers of the nodes on both ends of the link,
starting with the smaller ID number. Link ID numbers and supplemental roads are not shown on this illustration.