Which Port is used with Kerberos (HTTP) Authentication?

Kerberos authentication over HTTP typically uses port 88, which is the default port for the Kerberos Key Distribution Center (KDC) to handle authentication requests. Kerberos itself is a network authentication protocol designed to provide strong security in environments like Windows domains.

When Kerberos is used with HTTP, such as for Single Sign-On (SSO) in web applications (often referred to as "HTTP Negotiate" authentication), the authentication requests still rely on the underlying Kerberos infrastructure, which operates over port 88.

However, the actual HTTP traffic that leverages Kerberos authentication typically runs over the standard web ports, port 80 for HTTP or port 443 for HTTPS. In this case, Kerberos is used to authenticate the user, but the web traffic follows standard HTTP/HTTPS communication.