Key Exchange
Key exchange is a cryptographic protocol that allows two or more parties to securely establish a shared secret key over an insecure communication channel, such as the internet. It is a fundamental component of secure communication systems, enabling the encryption and decryption of data without pre-shared secrets. Common examples include Diffie-Hellman and its variants, which are widely used in protocols like TLS/SSL for web security.
Developers should learn key exchange when building secure applications that require encrypted communication, such as web servers, messaging apps, or VPNs, to prevent eavesdropping and man-in-the-middle attacks. It is essential in scenarios where parties cannot meet in person to share keys, such as in e-commerce, online banking, or IoT device authentication. Understanding key exchange helps implement robust security in protocols like HTTPS, SSH, and secure email.