          <---------- PREOF-capable DetNet IP --------------->
                                    ______
                          ____     /      \__
               ____      /     \__/          \____________
+----+      __/    \____/                                 \    +----+
|src |_____/                                               \___| dst|
+----+     \_______            DetNet network    __________/   +----+
                   \_______                    _/
                           \         __     __/
                            \_______/  \___/

                                       +------------+
             +---------------E1---+    |            |
+----+       |               |    +---R3---+        |          +----+
|src |------R1           +---+             |        E3----O----+ dst|
+----+       |           |                 E2-------+          +----+
             +----------R2                 |
                         +-----------------+