PP Presentation

• The only ambiguity is between frame m and m+1. If the sender times out too early, while an ack is on the way a dup frame will be sent. The ack arrives and the sender is fooled into thinking the ack is for the frame just sent (not the dup). If the next frame is is lost, the sender will not try to retransmit and the protocol fails. PAR can deadlock if the sender times out too early.

Previous slide

Next slide

Back to the first slide

View Graphic Version