Windows Authentication Overview (2024)

Applies to: Windows Server 2022, Windows Server 2019, Windows Server 2016

This navigation topic for the IT professional lists documentation resources for Windows authentication and logon technologies that include product evaluation, getting started guides, procedures, design and deployment guides, technical references, and command references.

Feature description

Authentication is a process for verifying the identity of an object, service or person. When you authenticate an object, the goal is to verify that the object is genuine. When you authenticate a service or person, the goal is to verify that the credentials presented are authentic.

In a networking context, authentication is the act of proving identity to a network application or resource. Typically, identity is proven by a cryptographic operation that uses either a key only the user knows - as with public key cryptography - or a shared key. The server side of the authentication exchange compares the signed data with a known cryptographic key to validate the authentication attempt.

Storing the cryptographic keys in a secure central location makes the authentication process scalable and maintainable. Active Directory Domain Services is the recommended and default technology for storing identity information (including the cryptographic keys that are the user's credentials). Active Directory is required for default NTLM and Kerberos implementations.

Authentication techniques range from a simple logon, which identifies users based on something that only the user knows - like a password, to more powerful security mechanisms that use something that the user has - like tokens, public key certificates, and biometrics. In a business environment, services or users might access multiple applications or resources on many types of servers within a single location or across multiple locations. For these reasons, authentication must support environments for other platforms and for other Windows operating systems.

The Windows operating system implements a default set of authentication protocols, including Kerberos, NTLM, Transport Layer Security/Secure Sockets Layer (TLS/SSL), and Digest, as part of an extensible architecture. In addition, some protocols are combined into authentication packages such as Negotiate and the Credential Security Support Provider. These protocols and packages enable authentication of users, computers, and services; the authentication process, in turn, enables authorized users and services to access resources in a secure manner.

For more information about Windows Authentication including

• Windows Authentication Concepts

• Windows Logon Scenarios

• Windows Authentication Architecture

• Security Support Provider Interface Architecture

• Credentials Processes in Windows Authentication

• Group Policy Settings Used in Windows Authentication

see the Windows Authentication Technical Overview.

Practical applications

Windows Authentication is used to verify that the information comes from a trusted source, whether from a person or computer object, such as another computer. Windows provides many different methods to achieve this goal as described below.

Software requirements

Windows Authentication is designed to be compatible with previous versions of the Windows operating system. However, improvements with each release are not necessarily applicable to previous versions. Refer to documentation about specific features for more information.

Server Manager information

Many authentication features can be configured using Group Policy, which can be installed using Server Manager. The Windows Biometric Framework feature is installed using Server Manager. Other server roles which are dependent upon authentication methods, such as Web Server (IIS) and Active Directory Domain Services, can also be installed using Server Manager.