+------------+
             +-----------E1----+    |            |
+----+       |            |    +---R3---+        |          +----+
|src |------R1        +---+             |        E3----O1---+ dst|
+----+       |        |                 E2-------+          +----+
             +-------R2                 |
                      +-----------------+

R: replication point (PRF)
E: elimination point (PEF)
O: ordering function (POF)