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  1. Senior Member gadav478's Avatar
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    #26
    Quote Originally Posted by hardstylewon View Post
    I couldn't have said it better.
    How do you go about this method? Just curious.
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  3. Senior Member
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    #27
    Quote Originally Posted by luke_bibby View Post
    172.20.0.0/28 or rather 172.20.0.0/255.255.255.240

    Class B address.
    Class B default mask = 255.255.0.0

    172.20.0.0 is subnetted by borrowing 12 bits from the host portion of the address (28 - 16 = 12).

    Number of subnets = 2^12 = 4096
    Number of usable hosts = (2^4) - 2 = 16 - 2 = 14
    I understand that 2 can't be used because the first and last ip, but why it -2 a 2nd time?
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  4. Professional Cat Herder ChickenNuggetz's Avatar
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    #28
    Quote Originally Posted by gbdavidx View Post
    I understand that 2 can't be used because the first and last ip, but why it -2 a 2nd time?
    I think you've misunderstood what he was doing. He's basically writing out his thought process. The 16 he gets is from calculating 2^4 and then he is subtracting 2 which gives him the final answer of 14. It wasnt exactly clear, but I understand what he was trying to show.
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