Questions

Which subnet is the host on?

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Which subnet is the host on?

scssnow
Given IP address 137.12.23.140
I need to support 259 subnets

Okay, I keep forgetting how to solve this and its going to be on the test next week. So I'm looking for some easy steps that are straight to the point.
So again, with any given IP address and subnet mask, I need to know what subnet a host is on.
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    0 Votes
    Dumphrey

    its the binary math for working this out.

    "So again, with any given IP address and subnet mask, I need to know what subnet a host is on."

    host address ANDed with mask will give you the network address. So as long as you can convert to binary and back you should be all good. They never tougt us ANDing (well it wa s mentioned in under 10 min) when I wa learning subnetting. Takes a few to get to terms with, but easier then counting and skipping etc...

    (anding: 1 and 1 = 1, 1 and 0 = 0, 0 and 0 = 0)
    so
    11100000 = 224 (last octet of ip address)
    00000000 = 0 (last octet of /24 netmask)
    ________

    00000000 = 0 the network address.

    Simple example but it works with vlsm as well.

    http://tinyurl.com/lqzjn

    Has some good overall info.

  • +
    0 Votes
    Dumphrey

    its the binary math for working this out.

    "So again, with any given IP address and subnet mask, I need to know what subnet a host is on."

    host address ANDed with mask will give you the network address. So as long as you can convert to binary and back you should be all good. They never tougt us ANDing (well it wa s mentioned in under 10 min) when I wa learning subnetting. Takes a few to get to terms with, but easier then counting and skipping etc...

    (anding: 1 and 1 = 1, 1 and 0 = 0, 0 and 0 = 0)
    so
    11100000 = 224 (last octet of ip address)
    00000000 = 0 (last octet of /24 netmask)
    ________

    00000000 = 0 the network address.

    Simple example but it works with vlsm as well.

    http://tinyurl.com/lqzjn

    Has some good overall info.