I'm from VietNam. I teach crypto, so i defenitely have knowledge Caesar Cipher, Affine Cipher, DES, AES, RSA, DSA, prime numbers, ... I also can programe in PHP language and others (C++, C#, ...)
I defenitely can do this assignment for you, (may be others in future).
If you reward to me, I'll do it and demo for you soon (2-5 days)
Message me please.