+-----+       +-----+       +-----+       +-----+       +-----+
 |  A  +-------+  B  +-------+  C  +-------+  D  +-------+  H  |
 +-----+       +--+--+       +--+--+       +--+--+       +-----+
                  |             |             |
                  |             |             |
               +--+--+       +--+--+       +--+--+
               |  E  +-------+  F  +-------+  G  |
               +-----+       +-----+       +-----+


      +--------+
      |IP(A->E)|
      +--------+                 +--------+        +--------+
      |  UDP   |                 |IP(E->G)|        |IP(G->H)|
      +--------+                 +--------+        +--------+
      |  L(G)  |                 |  UDP   |        |  UDP   |
      +--------+                 +--------+        +--------+
      |  L(H)  |                 |  L(H)  |        |Exp Null|
      +--------+                 +--------+        +--------+
      | Packet |     --->        | Packet |  --->  | Packet |
      +--------+                 +--------+        +--------+