Dictionary · Protocols and Ports
Kerberos
Identity · Advanced
A ticket-based authentication protocol. Users authenticate to a trusted key-distribution center and then present tickets to services instead of sending a password to every server.
You prove who you are once and receive tickets. Services check the ticket rather than collecting your password themselves. Clock accuracy is part of making the tickets believable.
Example: A domain user receives a ticket-granting ticket and later uses a service ticket to open a file share.
Ports
- TCP/UDP 88 — Ticket authentication
Common misconception
- Tickets are not the same as a certificate for a website, and skewed clocks can make valid tickets look expired.