Thomas Kunz
Systems and Computer Engineering
383
Link Level Retransmissions
An Early Study
nThe sender’s Retransmission Timeout (RTO) is a function of measured RTT (round-trip times)
–Link level retransmits increase RTT, therefore, RTO
nIf errors not frequent, RTO will not account for RTT variations due to link level retransmissions
–When errors occur, the sender may timeout & retransmit before link level retransmission is successful
–Sender and link layer both retransmit
–Duplicate retransmissions (interference) waste wireless bandwidth
–Timeouts also result in reduced congestion window