I am a self learner and tried to learn AES, so I have a book written in my native language. It has some practical examples about finite fields and AES. It has a question that asks me to calculate the byte substitution process in advanced encryption system in GF($2^8$).

The book ask for 10010011. I know that it is equal to $x^7+x^4+x+1$ in GF($2^8$), but there is not any example about what should be done in substitution layer. When I look at internet, the process proceed via S-box, but I do not know how to go further. I haven't worked with an S-box yet.

Can you help me with this example assignment so I can calculate the rest by myself?



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