Editing Key exchange (section)

===Diffie–Hellman key exchange ===
In 1976, Whitfield Diffie and Martin Hellman published a [[cryptographic protocol]] called the [[Diffie–Hellman key exchange]] (D–H) based on concepts developed by Hellman's PhD student [[Ralph Merkle]]. The protocol enables users to securely exchange secret keys even if an opponent is monitoring that communication channel. The D–H key exchange protocol, however, does not by itself address authentication (i.e. the problem of being sure of the actual identity of the person or 'entity' at the other end of the communication channel).  Authentication is crucial when an opponent can both monitor ''and alter'' messages within the communication channel (AKA [[Man-in-the-middle attack|man-in-the-middle]] or MITM attacks) and was addressed in the fourth section of the paper.<ref>{{cite journal|author1=Diffie, Whitfield|author2=Hellman, Martin E.|title=New Directions in Cryptography|journal=IEEE Transactions on Information Theory|date=November 1976|volume=IT-22|issue=6|pages=644–654|doi=10.1109/TIT.1976.1055638|url=https://ee.stanford.edu/%7Ehellman/publications/24.pdf}}</ref>