+------------+
                          | Application|
                          +------+-----+
                                 |
                        +--------+---------+
             +----------+SDN Controller/PCE+-----------+
             |          +--------^---------+           |
             |                   |                     |
             |                   |                     |
        PCEP |             BGP-LS|PCEP                 | PCEP
             |                   |                     |
             |                +--v---+                 |
             +----------------+R3(RR)+-----------------+
 PF12        |                +------+                 |         PF22
 PF11        |                                         |         PF21
+---+       +v-+          +--+          +--+         +-v+       +---+
|SW1+-------+R1+----------+R5+----------+R6+---------+R7+-------+SW2|
+---+       ++-+          +--+          +--+         +-++       +---+
             |                                         |
             |                                         |
             |            +--+          +--+           |
             +------------+R2+----------+R4+-----------+
                          +--+          +--+