The Go-Back-N protocol allows a sender to transmit N frames before requiring an acknowledgement. It has a transmit window size of N and receive window size of 1. While it does not wait for acknowledgement of each packet, resending frames multiple times can waste bandwidth. The Selective Repeat protocol only retransmits specifically identified lost frames, making more efficient use of bandwidth but with increased complexity compared to Go-Back-N.
The Go-Back-N protocol allows a sender to transmit N frames before requiring an acknowledgement. It has a transmit window size of N and receive window size of 1. While it does not wait for acknowledgement of each packet, resending frames multiple times can waste bandwidth. The Selective Repeat protocol only retransmits specifically identified lost frames, making more efficient use of bandwidth but with increased complexity compared to Go-Back-N.
The Go-Back-N protocol allows a sender to transmit N frames before requiring an acknowledgement. It has a transmit window size of N and receive window size of 1. While it does not wait for acknowledgement of each packet, resending frames multiple times can waste bandwidth. The Selective Repeat protocol only retransmits specifically identified lost frames, making more efficient use of bandwidth but with increased complexity compared to Go-Back-N.
The Go-Back-N protocol allows a sender to transmit N frames before requiring an acknowledgement. It has a transmit window size of N and receive window size of 1. While it does not wait for acknowledgement of each packet, resending frames multiple times can waste bandwidth. The Selective Repeat protocol only retransmits specifically identified lost frames, making more efficient use of bandwidth but with increased complexity compared to Go-Back-N.
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Specific instance of the automatic repeat request (ARQ) protocol
It can transmit N frames to the peer before requiring an ACK.
It is a special case of the general sliding window protocol with the
transmit window size of N receive window size of 1.
Advantage: Unlike waiting for an acknowledgement for each packet,
the connection is still being utilized as packets are being sent. Disadvantage: This method results in sending frames multiple times The Transmission Control Protocol uses a variant of Go-Back-N ARQ to ensure reliable transmission of data over the Internet Protocol, which does not provide guaranteed delivery of packets There are a few things to keep in mind when choosing a value for N: The sender must not transmit too fast. N should be bounded by the receiver’s ability to process packets. N must be smaller than the number of sequence numbers (if they are numbered from zero to N) to verify transmission in cases of any packet (any data or ACK packet) being dropped. Given the bounds presented in (1) and (2), choose N to be the largest number possible. It is part of the automatic repeat-request (ARQ). This is a general case of the sliding window protocol with both transmit and receive window sizes greater than 1.
The size of the sending and receiving windows must be equal, and half the maximum sequence number
It may be used as a protocol for the delivery and acknowledgement of
message units, OR It may be used as a protocol for the delivery of subdivided message sub-units. Selective Repeat is implemented in UDP transmission. Basis for Comparison Go-Back-N Selective Repeat
Retransmits all the frames that sent
Retransmits only those frames that are Basic after the frame which suspects to be suspected to lost or damaged. damaged or lost.
If error rate is high, it wastes a lot of Comparatively less bandwidth is wasted
Bandwidth Utilization bandwidth. in retransmitting.
More complex as it require to apply
Complexity Less complicated. extra logic and sorting and storage, at sender and receiver.
Window size N-1 <= (N+1)/2
Sorting is neither required at sender Receiver must be able to sort as it has
Sorting side nor at receiver side. to maintain the sequence of the frames. Receiver do not store the frames Receiver stores the frames received received after the damaged frame Storing after the damaged frame in the buffer until the damaged frame is until the damaged frame is replaced. retransmitted.
No searching of frame is required The sender must be able to search and
Searching neither on sender side nor on receiver select only the requested frame.
NAK number refer to the next expected
ACK Numbers NAK number refer to the frame lost. frame number.