Local Accounts or Central AAA?

About this interactive

AAA stands for authentication, authorization and accounting: verifying who someone is, deciding what they may access, and tracking what they did. The simplest way to log in to a router, switch or firewall is against its local database, a list of usernames and passwords kept on the device. That works for one or two devices. With a thousand, it becomes a management and security problem: every new account has to be created a thousand times, and when someone leaves, their account has to be removed from every device. Miss one, and the account still works. AAA services fix this by moving the accounts to a separate server. Each device passes the login to that server, which allows or denies it, so all the devices are on the same page. RADIUS, TACACS+ and Diameter are protocols that carry these requests. To sort a card, ask where the account lives: on the device itself, or on a server the device asks.

What you'll learn

Tell a device that checks logins against its own local database from one that asks a central AAA server
Explain why central AAA scales and is safer: one change to an account reaches every device that uses the server

Aligned to

CompTIA Security+

1.2 Summarize fundamental security concepts.

Key terms

Authentication, Authorization, and Accounting: Authentication, Authorization, and Accounting is a security framework that controls network access by verifying user identity, determining permitted actions, and logging activity for auditing and billing purposes.
Scalability: The ability of a system to handle increased load by adding resources without degrading performance.
Remote Authentication Dial-In User Service: RADIUS is a client-server networking protocol that provides centralized authentication, authorization, and accounting management for users connecting to network access points or VPN services.
Authentication Server: The server in a network access control framework (such as 802.1X) that validates supplicant credentials and grants or denies network access based on authentication policy. RADIUS is the most common authentication server protocol.

Topics

Interactive Streak Sort

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