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Forum Replies

  1. Rene,

    Thank you so much for your attention!!! Now I can understand better about this subject!

    and about:

    "The only thing to be aware of is that your summaries include networks that you “don’t have”."

    Yes, There is situation where is not possible to have a summarization so specific like example above, where we had that summarize 5 networks and it was need to use a block size of 8.

    I'm really grateful/thankful with your explanations. Thanks, thanks and thanks!!!


  2. Hi James,

    Where did you find this example? It's not on this page? :slight_smile:


  3. Rene,
    I got it off a ccna test page, but I believe I figured out the solution, what threw me off what the, it's similar to how you solved the other two.


  4. Hi Aaron, looks like this in binary:

    01111110 01011001 01111000 00000000

    Let's look at the third octet, since that's where 22nd bit is:

    120 = 01111110 01011001 01111000
    121 = 01111110 01011001 01111001
    122 = 01111110 01011001 01111010
    123 = 01111110 01011001 01111011

    So there it is, it matches,, and


  5. andrew says:

    CIDR and Supernetting are the same thing. This is where you can aggregate networks together into larger networks beyond their natural network boundary.

    Although Supernetting/CIDR might be considered a type of summarization, "summarization" generally is considered to be constrained by natural (classful) network boundaries. The distinction is somewhat subtle. Suppose you have the following:

    These could be summarized as because /27 is smaller than the natural /24 boundary.

    Now, if you had this:

    The supernet (or CIDR) of these would be because /23 is greater than the natural /24 boundary.

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