Sender                     Receiver
          |-----W=0,FCN=6,Seq=1----->|
          |-----W=0,FCN=5,Seq=2----->|
          |-----W=0,FCN=4,Seq=3----->|
          |-----W=0,FCN=3,Seq=4----->|
          |-----W=0,FCN=2,Seq=5----->|
          |-----W=0,FCN=1,Seq=6----->|
DL Enable |-----W=0,FCN=0,Seq=7----->|
      (no ACK)
          |-----W=1,FCN=6,Seq=8----->|
          |-----W=1,FCN=5,Seq=9----->|
          |-----W=1,FCN=4,Seq=10---->|
DL Enable |-----W=1,FCN=7,Seq=11---->| All fragments received
          | X--Compound ACK,W=1,C=1 -| C=1
DL Enable |-----W=1,FCN=7,Seq=13---->| RESEND ACK
          |<-Compound ACK,W=1,C=1 ---| C=1
        (End)