Sender                    Receiver
          |-----W=0,FCN=6,Seq=1----->|
          |-----W=0,FCN=5,Seq=2--X   |
          |-----W=0,FCN=4,Seq=3----->|
          |-----W=0,FCN=3,Seq=4--X   |
          |-----W=0,FCN=2,Seq=5----->|
          |-----W=0,FCN=1,Seq=6----->|
DL Enable |-----W=0,FCN=0,Seq=7--X   |
      (no ACK)
          |-----W=1,FCN=6,Seq=8----->|
          |-----W=1,FCN=5,Seq=9----->|                    __
          |-----W=1,FCN=4,Seq=10---->|                   |W=0
DL Enable |-----W=1,FCN=7,Seq=11---->| Missing Fragment<- FCN=5,Seq=2
          |<--Compound ACK,W=0,C=0 --| Bitmap:1010110    |FCN=3,Seq=4
          |-----W=0,FCN=5,Seq=13---->|                   |FCN=0,Seq=7
          |-----W=0,FCN=3,Seq=14---->|                    --
          |-----W=0,FCN=0,Seq=15---->| All fragments received
DL Enable |-----W=1,FCN=7,Seq=16---->|
          |<-Compound ACK,W=1,C=1 ---| C=1
        (End)