+-------------------------+
                |                         |
                |  Abstract Network Model |
                |                         |
                +------------+------------+
                             |
                   +---------+---------+
                   |                   |
            +------V------+     +------V------+
            |  Abstract   |     |  Inventory  |
            |  Network    |     |    Models   |
            |  Topology   |     |  (e.g., SAP |
            |   Model     |     |   Network   |
            |             |     |    Model)   |
            +-----+-------+     +-------------+
                  |
      +-----------+-----------+
      |           |           |
 +----V----+ +----V----+ +----V----+
 |TE Topo  | |L3 Topo  | |L2 Topo  |
 |  Model  | |  Model  | |  Model  | ...
 +---------+ +---------+ +---------+