Kex
In short
A key exchange is a cryptographic method used to share secret keys between two parties over a public channel. This process allows them to establish a secure connection for encrypted communication.
In plain words
It is a way for two people to agree on a secret code without anyone else seeing it. Even if someone listens to the conversation, they cannot figure out the secret code being shared.
A simple example
Alice and Bob use a mathematical formula to create a shared password. An eavesdropper sees the numbers they swap but cannot calculate the final password from them.
Why it matters
Without it, secure internet browsing and private messaging would be impossible. It ensures that sensitive data stays private even when sent across unsecure networks.
Easy to mix up
It is often confused with encryption itself, but key exchange is only the method used to share the tools needed for encryption.