Guide to Network Access Servers(NAS)

What is Network Access Server: A Network Access Server (NAS) is a single point of access to a remote resource. It serves as a gateway for users to connect to a network, serving as an access point to the internet or other networks. NAS systems are crucial components in network security, handling user authentication and authorization.

Why it is important: NAS is essential due to its role in controlling the access to networks. It ensures that only authenticated users gain access, thereby curbing unauthorized usage and potential threats. It also tracks user activities, which is crucial for monitoring network usage, detecting irregularities, and troubleshooting.

How it works: A NAS typically interacts with the user's device, commonly known as the client, and an authentication server. The client sends connection requests to the NAS, which then sends these to the authentication server. The authentication server verifies the credentials and informs the NAS whether to grant or deny access to the network based on the authentication result.

Exam Tips: Answering Questions on Network Access Servers:
1. Clearly understand the role of NAS in network security, including authentication and authorization processes.
2. Familiarize yourself with various types of NAS devices and their specific functions.
3. Be able to explain how a NAS interacts with client devices and authentication servers.
For instance, you might be asked to describe the process a NAS follows to authenticate a user's access request. In this scenario, you should explain how the NAS forwards the user's access request credentials to the authentication server which makes the access decision and relays it back to the NAS.