Kerberos

Kerberos is a network authentication protocol designed to provide secure authentication for client-server applications. It was developed by the Massachusetts Institute of Technology (MIT) in the late 1980s as part of Project Athena. The protocol uses secret-key cryptography and a trusted third party, known as the Key Distribution Center (KDC), to authenticate users and services within a network.

Kerberos operates by issuing tickets to clients that request access to services. These tickets are encrypted and can be securely transmitted over an insecure network. When a user logs in, the client requests a ticket from the KDC, which contains a session key. This session key is used to authenticate communication between the client and the requested service without transmitting passwords over the network. The protocol's name, "Kerberos," is derived from the Greek mythology character Cerberus, a three-headed dog that guards the underworld, symbolizing its role in safeguarding authentication processes. Its development at MIT was driven by the need for a robust security system as educational institutions began to rely more heavily on networked computing. Kerberos has evolved since its inception, with widespread adoption in major operating systems like Windows, macOS, and various UNIX-based systems. Its ability to provide strong authentication and mutual trust between users and services makes it a cornerstone of secure networked environments.