What is an Authentication Token?
An Authentication Token is a piece of data or information used to authenticate a user's identity during the authentication process. It serves as proof of the user's identity and is typically issued by an authentication server or identity provider upon successful authentication.
How an Authentication Token Functions
After a user successfully authenticates their identity (for example, by providing a username and password), the authentication server generates an authentication token. The authentication token is then issued to the user, either directly or through the application or service they are trying to access. When the user attempts to access a resource or service that requires authentication, they present the authentication token as proof of their identity. The receiving system verifies the authentication token to ensure its validity and authenticity. This may involve checking cryptographic signatures, expiry dates or other token properties. If the authentication token is valid and matches the expected criteria, access to the requested resource or service is granted.
Authentication tokens come in various forms, including the following:
Session Tokens
Temporary tokens are issued for the duration of a user's session after successful authentication. They typically expire after a certain period of inactivity or when the session ends.
Bearer Tokens
Tokens that grant access to specific resources or services without additional authentication. They are commonly used in OAuth 2.0 and similar authentication protocols.
JSON Web Tokens (JWT)
A type of token format commonly used in modern web applications for transmitting claims between parties. JWTs are self-contained, digitally signed, and can contain information about the user's identity and access permissions.
Authentication tokens provide several benefits, including improved security, scalability and user experience. By eliminating the need to repeatedly authenticate users for each request, tokens streamline the authentication process and reduce the risk of credential theft or interception. Also, tokens can carry additional information, such as user attributes or access permissions, enabling fine-grained access control and personalised user experiences.
