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  • Content created by Rene Molenaar (CCIE #41726)


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Forum Replies

  1. Hi Rene,
    Very Good article for Beginners.


  2. Hi,
    Under Class A subnetting section, the subnet mask should be instead of
    Typo I guess.

  3. Hi George,

    Let’s walk through this example together, that might help…

    First we need to figure out the network address and to do that, we need to take a close look at the subnet mask:

    The subnet mask defines how large each subnet is. You can do this in binary but I’ll use decimal since it’s faster. A quick method is to take the number 256 minus the subnet mask. We are looking at the 4th octet so that’s 248:

    256 - 248 = 8

    We now know that each subnet has 8 addresses. Let’s start counting from 0 to show you how it works:

    Subnet #1

    ... Continue reading in our forum

  4. Hi Rene,

    You are doing a good Job. I wanted to ask, in your example you have said is the first address for that block? I thought .104 is the network and the first usable address will start from 105? If you could clarify that for me. Thanks

  5. Ali,
    You are correct, and I have corrected the error. Nice catch.

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