+------------+
                | OSPF Link  |
                +------------+
                  |   |   |
                  v   |   v
     +-------------+  |  +-------------+
     | Interface 1 |  |  | Interface 2 |
     +-------------+  |  +-------------+
                   |  |   |
                   v  v   v
                +------------+
                | Phys. Link |
                +------------+