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An important property between sender and receiver windows

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• A very important property in Sliding Window protocols

  • Important property:

    The receiver window will always be: lined up with the sender window: or: ahead of the sender window: I.e.: the receiver window can never fall behind the sender window

    Reason:

    The receiver window will always slide foward before the sender window !!! The receiver window will slide when: the first data frame in the receiver window is received           This receive event will trigger the receiver to: send the ACK frame for the first data frame in the sender window !!!        The sender window will only slide when: this ACK frame is received         The sender window can only slide later in time !!!!

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  • Example Program: (Demo above code)                                                
    • Prog file: /home/cs455000/demo/SelAck/run

    How to run the program:

    Send 1 new frames