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In this video, we are going to learn the last
case of subnetting.

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In this case, we have 15 PC in our network.

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As usual, we are going to calculate the best
prefix we will use, The total IP, subnetmask,

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network IP, broadcast IP, and Range IP.

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Okay let’s just start.

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First let’s determine the best prefix for
15 PC.

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Let’s write the powers, 2 to the power of
1 is 2, 2 to the power of 2 is 4, 2 to the

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power of 3 is 8, 2 to the power of 4 is 16,
2 to the power of 5 is 32, and so on.

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Here now we already have 16 and 32, may be
some of you think that we can use 16 for 15 PC.

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But actually, this 16 will be minus by 2,
so the actual is only 14 PC.

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Why minus by 2?

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Because we will have network IP and broadcast
IP.

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And remember that Network and broadcast IP
never can be used.

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Once again, if the total IP 16, the IP that we
can used is only 14, this is not enough for 15 PC

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So we will use 2 to the power of 5.

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And the prefix is 32 minus by 5, which is
/27.

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Okay now we have the best prefix we can use.

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Next let’s determine which IP we will use.

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We can use either 10.0.0, or 172.16, or 192.168

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In this case, I will use the first range,
which is 10.

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Let’s say the IP is 10.10.10.0/27.

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Remember that the last number here will be
change between 0 until 255.

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And the third first number will be never change.

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And the prefix here is /27, this is result
of our calculation before.

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I think enough for this video, in the next
video, we are going to calculate total ip,

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subnetmask, network ip, broadcast ip and range
ip.

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Thankyou for watching and see you on the next
video