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Sliding Window Protocols. Piggybacking. Is a bi-directional data transmission technique. Frame arrives to destination . the ack attached to an outgoing data frame (using " ack " field in header). . Piggybacking. Piggybacking. Advantages:. More efficient (Why?). Cost (1 bit).
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Piggybacking Is a bi-directional data transmission technique. Frame arrives to destination • the ack attached to an outgoing data frame (using "ack" field in header).
Piggybacking Advantages: More efficient (Why?) Cost (1 bit) Disadvantages: How long to wait for a packet to piggyback? There is a problem. If the wait for longer than the sender's timeout period, the frame will be retransmitted (How To solve)
Piggybacking Receiver timeout enable (Individual ACK)
Sliding Window Protocols They are bidirectional protocols One-bit sliding window protocol Go back N protocol Selective repeat protocol
Sliding Window Protocols Two stations, A and B, connected via a full-duplex link Each side needs to send the data and acknowledgments to the other. ACK includes number of next frame expected Frames have sequence number 0 to maximum 2n- 1
Sliding Window Protocols Sender & receiver have buffer size of W transmitter sends up to W frames without ACK Window full (maximum window size reached) shut off network layer
One-bit Sliding Window Protocol Stop –and-Wait (What is meaning?) The maximum size of sender and receiver windows (?) Sequence number (0,1)
Go Back N Protocol Sender’s window size is W (W >1) It needs for multiple timers each outstanding frame
Go Back N Protocol 5 6 6 7