34 lines
985 B
Markdown
34 lines
985 B
Markdown
# VLSM Examples
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Say we have the IPs: 210.19.[14 -> 19].0/24
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We want to create to networks which support this many hosts
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## Part A
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* A: 1000 hosts
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* B: 500 hosts
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Doing A first(because it's bigger):
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Third octet in our IP has the bit pattern of `0000 11100`
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If we want to support 1000 hosts we need to borrow the last two bits of that pattern:
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> __problem__: one of those is 1 which means we can't borrow it as its part of our given network address.
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Thus this problem then can't be done given this information.
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If we had been given x.x..12.0 we could do it because 12's bit pattern is `0000 1100`, which leaves the last two bits as 0's that we can use for the hosts.
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## Part B
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This time we need to support 500 hosts so we need 9 bits for the hosts. This time we can use `x.x.14.0` as our network address
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Our mask is /23 `255.255.154.0`. This leaves our network address as `210.19.14.0`.
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* The first host is x.x.14.1
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* The last host is x.x.15.254
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* Broadcast is x.x.15.255
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