foodsmor.blogg.se - Sliding window protocol java program

Whenever the receiver receives a new frame, it generally places it at the end of a linked list.SR protocol implemented as a linked list which requires sorting at a receiver’s end.It also accepts the out-of-order frames which means sometimes it receives the unexpected sequence number frame then rather than discarding the frame, it keeps it in the sliding window.

Then, the sender again sends that frame to the receiver. Instead of directly discarding, it sends the negative acknowledgment to the sender. Additionally, this protocol also not accepts the corrupted frames and hence not silently discard them. Selective repeat protocol (SR) uses only independent acknowledgments only which means the receiver acknowledges each frame separately. In this protocol, the sender window size is always the same size as the receiver window size. Selective repeat protocol is the implementation of sliding window protocol. The efficiency of the Go-Back-N protocol is calculates as:Īlso Read: Difference between SQL and MySQL Selective Repeat ARQ: Go- back -N protocol silently discards the corrupted frames which means it simply rejects the faulty frame without taking any action.However, if required Go-back uses independent acknowledgments too.After that, the timer expires receiver sends the cumulative acknowledgment for all those frames which are not acknowledged at that moment.Further, each time receiver receives a new frame which in response generates a new acknowledgment timer.Go Back-N uses cumulative acknowledgments under which the receiver maintains an acknowledgment timer.

Here, in the protocol the size of the window is N and the size of the receiver window is always 1.

In this method, if one of the sent frames is encountered as corrupted, then all frames have to be sent again. This Go-Back-N Automatic Repeat Request is one of the data link protocol which uses a sliding window method. Sliding Window Protocol comprises of two types which are: In a sliding window protocol, optimal sender window size = 1 + 2a. In this, the sender just slides its window on receiving the acknowledgments from the receiver. The sliding window protocol is a flow control protocol. It measures the maximum number of frames that the sender sends to the receiver before receiving acceptance. The size of sending window regulates the sequence number of outbound frames and the size of a receiving window is obtained as the maximum number of frames received by the receiver at a time. Each frame has sent from the sequence number so that it can avoid the duplicity of data and maintain the consistency of data. The sequence numbers are numbered as modulo-n. This technique uses the contrivance of the sequence number. Hence the sliding window method is also called windowing. The sender has a buffer which is referred to as a sending window and on the other side, the receiver has a buffer which is called receiving window. In this protocol, there is one sender and receiver, where the sender has the flexibility to send many data frames before getting acknowledgment from the receiver.

2 Sliding Window Protocol comprises of two types which are:.