A: packet with A coloring
B: packet with B coloring

         |           |           |           |           |
         |           |    Traffic Flow       |           |
 ------------------------------------------------------------------->
  BBBBBBB AAAAAAAAAAA BBBBBBBBBBB AAAAAAAAAAA BBBBBBBBBBB AAAAAAA
 ------------------------------------------------------------------->
    ...  |  Block 5  |  Block 4  |  Block 3  |  Block 2  |  Block 1  
         |           |           |           |           |