Write a systematic review article about the up-to-date state of the art of the Diffie- Hellman Key Exchange Algorithm and the Discrete Logarithm Problem. What is it? Where is it used (in Computers, Cryptology) use a minimum of 50 references and cite the references according to the Vancouver style system. Also the reference list at the end of the manuscript must be according to the Vancouver system. Furthermore the manuscript must have the sections introduction, material and methods (which search engienes have been used, which search terms were used), results section and discussion section. Furthermore a structured abstract is needed.  Explain the mathematics of Diffie Hellmann and explain the discrete logarithm problem and its relation to Diffie Hellmann.