Alternate representation


   [Seq=0,Ack=100,Len=40,WS=200] ->

<- [Seq=100,Ack=40,Len=0,WS=300]   

   [Seq=40,Ack=100,Len=40,WS=200] ->





   [Seq=80,Ack=100,Len=40,WS=200] ->

<- [Seq=100,Ack=40,Len=0,WS=300]   

   [Seq=40,Ack=100,Len=40,WS=200] ->

<- [Seq=100,Ack=120,Len=0,WS=300]