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Just wrote a examn about IPs an totally fucked it up. I hate subnet masks. SERIOUSLY, FUCK THEM

AAAHHHH fuuuuuu

💔

Comments
  • 0
    I loved that stuff in my Networking class! Lol
  • 1
    Its the math that always screws me over
  • 0
    @Minzkraut Just curious, do you do it the "block size" way?
  • 1
    @boomi I'm not sure what you mean
  • 1
    @Minzkraut

    I just remember these lists (ignore the periods and bad formatting ):
    128 192 224 240 248 252 254 255
    /25 /26. /27. /28. /29. /30. /31 /32
    128. 64. 32. 16. 8. 4. 2. 1

    So, we know any /26 has a block size (or range of addresses) of 64. Just increment until you land in the range where the address is:

    Arbitrary IP/mask: 123.65.34.187/26

    123.65.34.0
    123.65.34.64
    123.65.34.128. <====
    123.65.34.192

    Subnet ID is .128, broadcast is .191.

    The first list, 128 192 224 240 248 252 254 255, is used if you get a subnet in DDN instead of slash notation. E.g. 255.255.255.192 .

    256 - 192 = 64

    That being said, I too suck at math , and have difficulty with not screwing up basic addition in my head. Depending on how you were taught to do it though, this might be substantially easier.
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