Software → Security
Key Exchange
A method for two parties to agree on cryptographic keys over an insecure communication channel.
Motivation
Key exchange solves the problem of agreeing on shared secret material over an insecure network.
Where it fits
Key Exchange belongs to cryptography and secure protocols.
Mental model
A key exchange lets two parties derive keys used for faster symmetric encryption.
Common mistakes
- Sending the final symmetric key directly.
- Ignoring authentication and man-in-the-middle risks.
Related concepts
Key Exchange connects to Diffie-Hellman, TLS, public-key cryptography, and symmetric encryption.