For anyone wondering m is the position of each letter in the alphabet, but because of numerical representation A has the position 0. So for A B C D E F G H I ... H is in the 7th position so for H m =7 and I is in the 8th position so for I m = 8 0 1 2 3 4 5 6 7 8
Great explanation... just that you included 9 as the options for the encryption key .. 9 is not a prime number. So it can’t be used as an option .. but overall amazing explanation for the RSA concept
What about when you got a public key to show, typical what PGP would generate? A typical key-generation require you to make and remember the password. Noone remember all the characters of the private or public key, they are just two text files anyway. The key exchange is fascinating and also how they are made. Keys of 512bits or more. Pity the calculating force of regular comuters doesnt enable such to be shown ;)
Think of the modulus operation like a circle. Lets take this example X mod N. N being a positive integer. That means that the values that we can get by using this operation are the integers inside this interval [0,N-1]. Now why do we need to think it like a circle. If I go from 0 to N-1 by applying the modulus operation we get the same value. If I set X to N then the modulus operation will throw 0. If N+1 then 1. So it is like a circle. We start again from 0 after going for bigger values than N. By using the circularity of the operation we can write X = m(N) + v; Where m is a multiplication factor of N and v is a value inside the interval that we defined before. The modulus operation will remove the m times N part from your X always. Now what happens if we make m negative? We can easily readjust the equation by adding multiplications of N in order to make the value positive. For your comment now -17 mod 40 = (-17 + 40) mod 40 = 23 mod 40 The circle will be complete if we use the difference operator 23 - (-17) = 40
It is the corresponding thing called the ascci value for characters .each character and symbol or number in english is represent in an specific ascci value so we can use it in such things and for example programming or information security
