In the previous video, we already learn how to find the best prefix that we can use in 2
the computer network. 3
And as I said, in this video we are going to learn with another case to find the best 4
prefix we can use. 5
Let’s say here we have a computer network that consists of 60 computers. 6
The question is, which prefix is the best we can use? 7
Now, pause the video and try to calculate it first by your self. 8
After you find the answer, you can continue watching this video and see if your answer 9
is correct or no. 10
Okay, how? 11
Do you find the best prefix for 60 computers? 12
Now let’s take a look at my explanation. 13
First, let’s write the powers that we do in the previous video. 14
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 15
of 3 is 4 multiply by 2, which is 8, 2 to the power of 4 is 8 multiply by 2, which is 16 16
2 to the power of 5 is 16 multiply by 2 which is 32. 17
2 to the power of 6 is 32 multiply by 2, which is 64. 18
2 to the power of 7 is 64 multiply by 2 which is 128, and last, 2 to the power of 8 is 128 19
multiply by 2, which is 256. 20
Now let’s find the best for 60 computers. 21
If we see until 2 to the power of 5, here we know that the total IP is still 32, 22
this not enough. 23
But 2 to the power of 6 is 64, and this is enough for 60 computers. 24
So the best prefix for 60 PC is 32 minus 6, which is /26. 25
Another example, let’s say here we have a computer network that consist of 100 computers. 26
Which pefix is the best to use? 27
We can just see the power calculation that we already do. 28
The answer is 2 to the power of 7, which is 128. 29
If we use 2 to the power of 6, this is not enough, and if we use 2 to the power of 8, 30
this is to much. 31
So the best is, 2 to the power of 7. 32
And the prefix will be 32 minus 7, which is /25 33
Okay now I hope you really understand how to find the best prefix we can use in the 34
computer network. 35
Thankyou for watching and see you in the next video!