... T=5 Data[0] Data[3] sent Data[0] Data[3] arrive at R Data arrive at B; ACK[0] ACK[3] start back ACKs arrive at R ACKs arrive at A; Data[4] Data[7] sent Data arrive at R A sends frames 1-4 Frame[1] ... arrives at R; Data[1] sent T=2 Data[0] arrives at B; ACK[0] starts back; Data[2] sent T=3 ACK[0] arrives at R; Data[3] sent T=4 ACK[0] arrives at A; Data[4] sent T=5 ACK[1] arrives at A; Data[5] sent ... now DATA[3] DATA[5] The sender times out and resends DATA[0], DATA[1], DATA[2] For convenience, assume DATA[1] and DATA[2] are lost The receiver accepts DATA[0] as DATA[5], because they have the...