Neil Rieck

Waterloo, Ontario, Canada.

https://neilrieck.net

caveat: this demo sometimes breaks at this hobbyist site. If you notice any problems then please send me an email here

Additional information for inquiring minds

- Overview
- The Diffie-Hellman algorithm occurs as part of the symmetric key cryptography handshake (the same key is used to encrypt and decrypt). Think about your school locker padlock where the same combination (er, key) is used to both lock and unlock.
- Eve, the eavesdropper can see a few things (RED) which could be a worrisome for those people who think that a super computer could be used to play along.
- However, if this handshake is concealed by asymmetric
key cryptography (also known as
**public key cryptography**) where a pubic key (which is derived from the server's certificate) is used to encrypt but a private key is used to decrypt, then Eve will see no part of the symmetric handshake. - Why not use asymmetric keys all the time?
- first off, asymmetric key cryptography is CPU intensive while symmetric key cryptography is much less so.
- secondly, there is an added benefit to using two levels of obfuscation.

- Source Code:
- python: notes - for people new to python programming
- diffie-hellman: standalone - for people curious about the Diffie-Hellman algorithm (written in Python3)
- difffe-hellman: web - for people curious about client-server web applications (written in Python3)