Forum Replies

  1. Hi Zaman,

    Originally the window size is a 16 bit value so the largest window size would be 65535. We couldn’t add more bits to the TCP header but it was possible to reassign the purpose of those 16 bits.

    What we do nowadays is that we use a scaling factor so that we can use higher window sizes.

    For example, the window size value is 400 and the scaling factor is 64.

    400 x 64 = 25600

    In my lesson one of the screenshots also showed a windows size of 132480.

    Window size value = 2070
    Window size scaling factor = 64

    2070 x 64 = 132480

    Here’s a short explanation of th

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  2. Hello Hussein!

    First lets take a look and see what is meant by the window size: The window size indicates the size of a device’s receive buffer for the particular connection. In other words, window size represents how much data a device can handle from its peer at one time before it is passed to the application layer. This buffer size can change based on the hardware being used (physical memory available on the NIC for buffering for example) as well as by the total number of TCP sessions the device is taking part in at any given time. Of course this window s

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  3. Hello Azm

    Yes, these numbers can be confusing. Here is an attempt to clarify these parameters:

    The first thing to keep in mind is that in any TCP communication, there are actually TWO sequence numbers and TWO acknowledgement numbers: those of each party in the exchange of data. For the sake of this example, and for the diagram below, let’s call these SNL and SNR for Sequence Number Left and Sequence Number Right for the left and right hosts. Similarly, the acknowledgement numbers will be called ANL and ANR.

    Note, these abbreviations are my own and are not ge

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  4. Hello AZM

    I can understand the confusion. Keep in mind that the window size, the sequence number and the number of segments sent are somewhat independent from each other. What do I mean?

    Well, let’s say we have a window size of 21000 bytes. It is very unlikely that this will all be sent in one segment. It will definitely be split into several segments. The window size is “the number of bytes sent before an acknowledgement is required from the receiver.” These bytes can be sent in one or more segments. So, let’s take the following example:

    Host A is sendi

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  5. Hello Juan

    Just like any other protocol communicating on the network, BGP requires the appropriate MTU sizes to be set in order for communication to occur successfully. If you have to tune the MTU value to get BGP to work then it seems that BGP is sending IP packets larger than the interface MTU that have the DF set to 1, which means to not fragment. By adjusting the (IP or interface MTU) of the subinterface, you are essentially adjusting the allowable MTUs such that the IP MTU will be small enough to fit into the interface MTU. It also depends on what other

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