In the infrastructure, there can be different types of authentication protocols in use. Active Directory uses Kerberos version 5 as the authentication protocol in order to provide authentication between the server and the client. Kerberos v5 became the default authentication protocol for Windows Server from Windows Server 2003. It is an open standard, and it provides interoperability with other systems that use the same standards. Before we look into improvements in AD DS security, it is important to understand how Active Directory authentication works with Kerberos.

The Kerberos protocol is built to protect authentication between the server and the client in an open network where other systems are connected as well. The main concept behind authentication is that two parties have agreed on a password (secret), and both use it to identify and verify...