Question :

Alice and Bob create a key using the key exchange. They agree upon prime modulo p. and Hellman y, p and primitive root g Bob privately choose integers r and Alice respectively. They compute a private key k using the method discussed in class

If Eve the eavesdropper can see p and g (this information is public), explain why she cannot compute Alice and Bob's key k. In other words, explain why the Diffie-Hellman key exchange is Secure.