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In the previous video, we already learn how
to find the best prefix that we can use in

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the computer network.

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And as I said, in this video we are going
to learn with another case to find the best

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prefix we can use.

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Let’s say here we have a computer network
that consists of 60 computers.

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The question is, which prefix is the best
we can use?

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Now, pause the video and try to calculate
it first by your self.

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After you find the answer, you can continue
watching this video and see if your answer

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is correct or no.

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Okay, how?

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Do you find the best prefix for 60 computers?

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Now let’s take a look at my explanation.

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First, let’s write the powers that we do
in the previous video.

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2 to the power of 1 is 2, 2 to the power 2
is 2 multiply by 2, which is 4, 2 to the power

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of 3 is 4 multiply by 2, which is 8, 2 to
the power of 4 is 8 multiply by 2, which is 16

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2 to the power of 5 is 16 multiply by 2 which
is 32.

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2 to the power of 6 is 32 multiply by 2, which
is 64.

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2 to the power of 7 is 64 multiply by 2 which
is 128, and last, 2 to the power of 8 is 128

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multiply by 2, which is 256.

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Now let’s find the best for 60 computers.

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If we see until 2 to the power of 5, here
we know that the total IP is still 32,

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this not enough.

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But 2 to the power of 6 is 64, and this is
enough for 60 computers.

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So the best prefix for 60 PC is 32 minus 6,
which is /26.

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Another example, let’s say here we have
a computer network that consist of 100 computers.

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Which pefix is the best to use?

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We can just see the power calculation that
we already do.

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The answer is 2 to the power of 7, which is
128.

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If we use 2 to the power of 6, this is not
enough, and if we use 2 to the power of 8,

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this is to much.

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So the best is, 2 to the power of 7.

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And the prefix will be 32 minus 7, which is
/25

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Okay now I hope you really understand how
to find the best prefix we can use in the

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computer network.

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Thankyou for watching and see you in the next
video!