Consider the figure below in which a TCP sender and receiver communicate over a connection in which the sender$->$receiver segments may be lost. The TCP sender sends an initial window of $4$ segments. Suppose the initial value of the sender$->$receiver sequence number is $106$ and the first $4$ segments each contain $576$ bytes. The delay between the sender and receiver is $7$ time units, and so the first segment arrives at the receiver at t$=8.$ As shown in the figure below, $2$ of the $4$ segment$($s$)$ are lost between the segment and receiver.