Assigning subnet masks to subnetworks?

Given network ID and default mask, how would I assign subnet masks to each of the six subnetworks? I have no idea how to do the work.

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3 Answers

  • BigE
    Lv 7
    8 months ago

    This sort of misleading, the router links are point to points not hosts. So I consider those to be useable ips, not hosts.

    So lets just do that, even though one tends to put the large networks on the low end, one can gather together similar networks if they fill a block.

    So a /30, is 2 bits, the last 2, or 4 ips.  Since we want to use the last ips, that would be, spanning

    The network is

    The first router interface is

    The second router interface is

    broadcast is

    Take each network, see what block you need (how bit a power of 2 you need)

    and fit it into a /24, even if you have to draw it out. They can't overlap and must be encompassed by a power of 2. So 100 hosts can only be satisfied by 128 or 2^7, or a /25.  That means the network

    is (if we say we want big blocks low) meaning ips (similar to above).

    Its easier to visualize than to calculate, but it is all digital math that drives the rules.

    Use this to check, but understand it:

  • VP
    Lv 7
    8 months ago

    Remember the following:

    Don't abandon your questions.

  • 8 months ago

    So, how does the existing netmask work?  when you've figured that out, all you have to do is figure out how to further refine this for your subnets!

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