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  1. Amruta,
    This has to do with how the sequence number is incremented during the TCP session. Let’s say Client A is requesting 900 Bytes of data from Server 1. Once Server 1 starts to send the actual data to Client A, the length of the payload of what is being sent directly influences the next sequence number.

    So, let’s say the current Sequence number is 1, and the Server sends Client A, 300 Bytes. This means the sequence number will now be 301 (the original sequence number plus the amount of data in the payload that was just sent). Now, let’s say, after Clien

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  2. Hello Manami

    To understand the function of the PSH flag, it is important to first understand how TCP buffers data. TCP operates at layer four of the OSI model. To allow applications to read from and write to a TCP session, buffers are implemented on both sides of a TCP connection in both directions.

    Buffers allow for more efficient transfer of data when sending multiple segments of maximum size, such as when sending a large file. TCP will wait until a segment reaches its maximum size before sending it on its way. There are however some applications where this

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  3. Hello Mohammad

    When a TCP session is in progress, the sequence numbers are used to keep track of the number of bytes that have been transmitted within the session. When 100 bytes are sent from host A to host B, host B will respond with an ACK that is incremented by 100. If this is the beginning of the transaction and we started with a sequence number of 0, then the ACK that host B will send will be 100 indicating that the amount of data that has been received so far is 100 bytes.

    During the three way handshake, the first SYN packet is sent with an initial seq

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  4. Hello Hussein.

    First of all the sequence number doesn’t indicate how much data is sent, but the difference between the original sequence number and the acknowledgement number sent back to the reciever indicates the amount of data that has been sent in one window.

    Your first two questions have to do with something called windowing which is a flow control mechanism of TCP. Specifically, when a TCP session begins, the sequence number is chosen randomly. For example, let’s say the initial sequence number is 100588. During the initial handshake, the window size i

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  5. Hello Hussein

    Unfortunately there isn’t. Because the window size is always going to be much much smaller than the largest available sequence number, it will never reset to zero within a single segment. Segments are always many many orders of magnitude smaller. Only the hosts between them keep track of when the counter resets to zero. Even when it does, they only detect it at that specific segment. Once the segment is received and acknowledged, there is no need to keep track of the resetting of the counter from the host’s point of view.

    If you want to keep

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