I am thinking a lot of time about this.I am so sorry for my English.
I am making a computer control program.About controlling the fans/water pump/LEDs/beeper,etc.
I am going to use nrf24l01+ for making the wireless control.
I have to prevent the hacker from who want to make "man in the middle"(aka replay attack,right?) .
I am thinking about AES/SipHack.But I don't know these things at all,and message authentication.How to do it
I used some libraries.But when I enter a same number.It gave me the same code(AES).About the Siphack I don't know how to use it at all.
I had thought about exchanging the random number.But I think that is too easy to crack. So Please help me about this. I just a student in high school.I don't know these thing at all.