Receiver is A , and sender is B
The receiver sets the window size to 1000, and B sends segments.
Assume that segment 500 to 521 is lost.
Then receiver A would send an
ack of 501 to the sender. Once the sender receives the
ack of 501 it will then start sending segments 501 to 1000 again.
Does the sender send all 501 upto 1000 without expecting a acknowledgement in the middle?