The receiver records the sequence number of the earliest incorrect or un-received frame. The maximum number of frames that can be sent depends upon the size of the sending window. Selective Repeat protocol provides for sending multiple frames depending upon the availability of frames in the sending window, even if it does not receive acknowledgement for any frame in the interim. For example, if the sequence number is from 0 – 15, the window size will be 8. The size is half the maximum sequence number of the frame. It uses two windows of equal size: a sending window that stores the frames to be sent and a receiving window that stores the frames receive by the receiver. Here, only the erroneous or lost frames are retransmitted, while the good frames are received and buffered. Selective repeat protocol, also called Selective Repeat ARQ (Automatic Repeat reQuest), is a data link layer protocol that uses sliding window method for reliable delivery of data frames.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |