What user authentication method is recommended for groups with more than 1000 users?

RADIUS (Remote Authentication Dial-In User Service) is particularly recommended for environments with a large number of users, such as those exceeding 1000, due to its scalability and efficiency in handling user authentication requests. RADIUS operates on a client-server model that allows multiple access points to authenticate against a centralized server, making it well-suited for organizations with extensive user bases.

RADIUS also supports network access control, which is essential for maintaining security across a large number of users. It allows for various forms of authentication and provides accounting capabilities, enabling organizations to track user access and activity.

Furthermore, RADIUS can integrate easily with other systems and networks, which is advantageous in larger deployments where diverse technologies might need to work together seamlessly. This characteristic ensures that it remains effective in managing a high volume of authentication requests, maintaining both performance and reliability.

In contrast, while other methods like LDAP, Kerberos, and CAS have their own advantages, they may not be as efficient or scalable for large user groups compared to RADIUS. For instance, LDAP is directory-based and typically used for query operations on large databases rather than handling the high volume of authentication requests efficiently in real-time. Kerberos, although secure, involves more complex ticketing mechanisms which can introduce