Section 3.4 Flashcards
What is meant by a cumulative acknowledgment, ACK(n)?
A cumulative ACK(n) acks all packets with a sequence number up to and including n as being received.
Which of the following statements about pipelining are true?
With a pipelined sender, there may be transmitted packets “in flight” – propagating through the channel – packets that the sender has sent but that the receiver has not yet received.
A pipelined sender can have transmitted multiple packets for which the sender has yet to receive an ACK from the receiver.
What are some reasons for discarding received-but- out-of-sequence packets at the receiver in GBN?
The sender will resend that packet in any case.
The implementation at the receiver is simpler.
What are some reasons for not discarding received-but- out-of-sequence packets at the receiver in GBN?
Even though that packet will be retransmitted, its next retransmission could be corrupted, so don’t discard a perfectly well-received packet, silly!
