part 1
000000000000000000000000000000000 data
l l window
part 2
11110000000000000000000000000000000 data
l l window
part 3
11110000000000000000000000000000000 data
l lwindow
part 4
11111001100000000000000000000000000 data
l lwindow
part 5
11111101100000000000000000000000000 data
1 1window
....
and so on
do you understand ?