tp GO-BACK-N PROTOCOL DONE BY: STEFFY.D(140071601072) SHEREEN FATHIMA.A(140071601068) TASNIM TABASUM.R(140071601080) COMPUTER NETWORKS LAB B.S.ABDUR RAHMAN UNIVER… Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising.
To implement flow control in a network Design a Go-Back-N ARQ (Automatic Repeat Request) protocol that uses piggybacking method whose window size is 2. The thing which should be kept in mind is that the time out timer at the sender node must be greater than the acknowledgment timer. Go-Back-N ARQ. Go Back N and Selective Repeat are the implementations of sliding window protocol. Before you go through this article, make sure that you have gone through the previous article on The two well known implementations of sliding window protocol are-In this article, we will discuss about Go back N protocol.Go back N protocol is an implementation of a sliding window protocol.The features and working of this protocol are explained in the following points-“Simply rejecting the frame and not taking any action”(like not sending a NACK to the sender to send the correct frame)Efficiency of any flow control protocol is given by-Watch video lectures by visiting our YouTube channel Liked this article? Share it with your friends and classmates now-Sliding Window Protocols in computer networks are the flow control protocols.
The thing which should be kept in mind is that the time out timer at the sender node must be greater than the acknowledgment timer. In Go-Back-N ARQ, N is the sender window size, which we can see in the above example was 5. In computer networking, there are various flow control protocols- In this article, we will discuss about sliding window protocol. Go Back N ARQ Protocol in Hindi - Data Communication and Networking Lectures in Hindi - Duration: 10:56. Go-Back-N ARQ is a form of ARQ protocol in which the sender continuously sends a number of packets (determined by the duration of transmission window) without receiving an ACK signal from the receiver. It can transmit N frames to the peer before requiring an ACK. If N=1, then our system reduces to Stop & Wait protocol.
Once the sender has sent all the frames in its window, it makes sure that it has then received all the feedbacks of the transmitted data packets, if in any case, it hasn't received a feedback of any data packet and the time out timer expires, it then resends all the data packets again, starting from the lost data packet to the final data packet.Consider a sender has to send data packets indexing from Now to find the effective bandwidth (or throughput),Effective bandwidth = efficiency * bandwidth, which means,There are basically 2 types of feedbacks/acknowledgments:Go-Back-N ARQ uses a cumulative acknowledgment technique, which means receiver starts an acknowledgment timer whenever it receives a data packet which is fixed & when it expires, it will transmit a cumulative acknowledgment for the number of data packets received in that interval of time out timer. Once the sender has sent all the frames in its window, it makes sure that it has then received all the feedbacks of the transmitted data packets, if in any case, it hasn't received a feedback of any data packet and the time out timer expires, it then resends all the data packets again, starting from the lost data packet to the final data packet.Consider a sender has to send data packets indexing from Now to find the effective bandwidth (or throughput),Effective bandwidth = efficiency * bandwidth, which means,There are basically 2 types of feedbacks/acknowledgments:Go-Back-N ARQ uses a cumulative acknowledgment technique, which means receiver starts an acknowledgment timer whenever it receives a data packet which is fixed & when it expires, it will transmit a cumulative acknowledgment for the number of data packets received in that interval of time out timer. In computer networking, there are various flow control protocols-In this article, we will discuss about sliding window protocol.Thus, to achieve 100% efficiency, window size of the sender must be 1+2a.Minimum number of bits required in sequence number field = ⌈logThe two well known implementations of sliding window protocol are-Efficiency of any flow control protocol may be expressed as-If transmission delay and propagation delay in a sliding window protocol are 1 msec and 49.5 msec respectively, then-Minimum number of bits required in the sequence number fieldMinimum number of bits required in the sequence number field = 7If only 6 bits are reserved in the sequence number field, then-= Sender window size in the protocol / Optimal sender window sizeIf transmission delay and propagation delay in a sliding window protocol are 1 msec and 99.5 msec respectively, then-Minimum number of bits required in the sequence number fieldMinimum number of bits required in the sequence number field = 8If only 6 bits are reserved in the sequence number field, then-= Sender window size in the protocol / Optimal sender window sizeTo gain better understanding about sliding window protocol,Watch video lectures by visiting our YouTube channel Liked this article?
Share it with your friends and classmates now-Go back N is an implementation of Sliding Window Protocol. Where tp is propagation delay and tt is the transmission delay Easy Engineering Classes 161,947 views … In Go back N, Consider a frame being sent to the receiver is lost on the way.
Now the receiver's duty is to keep the track of the sequence number of the next frame it expects to receive and sends the feedback after every data packet it receives.
The selective repeat protocol retransmits only that frame which is damaged or lost.