NAK free reliable  data transfer protocol

Reliable  data transfer  over a loss  channel  with bit error  rdt3.0 figure shows the  sender FSM for rdt 3.0 a protocols that  reliable data  transfer over a  channel  that can corrupt or loss  packets: figure shows  how the  protocols operates with  no lost  or delayed packets and how it handles lost data  packets. In figure time moves forward  from the top of the diagram toward the bottom of the diagram note  that a receive time  for a packet  is necessarily later than the  send time  for a  packet  as a result of transmission  and propagation delays. In figure and the send side brackets indicate the  times  at which a time  is set and later times out. Because packet  sequence numbers alternate between  0 an 1 protocols rdt 3.2  sometimes  knows as the  alternating bit  protocols.

                                                                           figure rdt sender