Cryptography

Could anyone please explain how to calculate the index of coincidence of the cipher below?

MXBOGKVDIGZINNVVCIJHH

Thanks!

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Comments

WilliamK99

Is this for a homework assignment?

TrainingDaze

Google is your friend

froufrou123

WilliamK99 wrote: »

Is this for a homework assignment?

Homework assignment is alot more complex, this is just a part of it. I've tried every google source, no one seems to have a clear explanation. Well, will ask the prof, thanks.

froufrou123

TrainingDaze wrote: »

Google is your friend

The answers in that source conflicted that of my class presentation's. That's why it wasn't clear to me.

froufrou123

It was so easy, for those learning follow this formula

IC = SUM of (x-y) / N*(N-1)

where (in cipher text)
x = freq. of each letter
y = x-1
N = number of letters

To confirm your IC use the following link:

CORE 139 S04: Index of Coincidence Tool

Hope it helps!