What You Need To Know About Radius Server?

An example of an application layer client-server networking protocol is the Remote Authentication Dial-In User Service (RADIUS). The free RADIUS protocol requires a RADIUS Server and RADIUS Clients. Continue reading to learn more about Radius.

 What Exactly Is Radius?

Authentication, authorization, and accounting (AAA) for distant users who access network services are managed using the networking protocol known as RADIUS (Remote Authentication Dial-In User Service). It offers a centralized way to manage network access control. It can identify people logging on to a network using different types of hardware, such as routers, firewalls, and VPNs.

 The RADIUS protocol calls for both a FreeRADIUS Server and RADIUS Clients.

For remote users who access a network, a RADIUS server is a central server that offers authentication and authorization services. It takes requests for authentication from RADIUS clients, including routers, firewalls, or VPNs, verifies the user's credentials, and then sends the client an authorization decision.

On the other hand, a RADIUS client is a device that communicates with a RADIUS server to request authentication. The client is in charge of transmitting user credentials to the server for validation and receiving authorization decisions from the server. It serves as a middleman between the remote user and the RADIUS server.

 In conclusion, a RADIUS server offers AAA services, whereas a RADIUS client requests these services on behalf of remote users.

 What is the function of RADIUS Server Authentication?

The RADIUS server compares supplied information with a central database for user verification. After the RADIUS client sends its credentials, the server checks them against a central authentication database. If the certificates are valid, the client can access data. As an illustration, consider access control lists (ACLs), which specify which networks and resources each user can access.

 A RADIUS Client's first order of business is to use the credentials provided to attempt authentication. The client then sends an Access-Request message to the RADIUS Server containing the credentials.

 RADIUS Servers employ an external database to validate user IDs (such as Active Directory).

 When a user's credentials are checked against the RADIUS Server's database, it will pull in additional data if a match is found.

 At login, the RADIUS server checks to verify if applicable access policies or profiles cover the user. In that case, an Access-Challenge request and a prompt to use Multi-Factor Authentication (if it is turned on) will be sent.

The Access Challenge can be answered with the input of a one-time password (OTP) or the acceptance of a push notification. The Radius server can see if everything is in order with this response.

 The RADIUS Server will send back an Access-Accept message if it is happy with your reply.

 An Access-Reject message is returned, and the transaction is canceled if RADIUS gets a server answer that does not follow a policy or is otherwise invalid. They will be locked out of the system and unable to access it.

 While sending an Access-Accept communication, both parties must include a Filter ID and a secret. A notification must match the shared secret to be accepted by the RADIUS Client.

 To determine if the shared secret is a match, the client looks at the value of the Filter ID attribute. The user can be added to a specified RADIUS Group by the RADIUS Client with this Filter ID. Users can now go online.

 Methods of RADIUS Server Authentication

There are several methods of user authentication available via the RADIUS server. When given the authenticated user's original username and password, it can support various authentication protocols.

 PAP uses the PPP configuration files and the PAP database to set up authentication. PAP is a login system that is functionally equivalent to the UNIX login software. To be clear, PAP does not grant the user shell access.

 CHAP -In the challenge and answer phase of the Challenge-Handshake Authentication Protocol (CHAP), the authenticator asks for identification information from the caller. A random number and the authenticator's unique ID make up the challenge. Using the ID, random number, and CHAP security credentials, the caller creates the answer (handshake) to send to the peer.

 MS-CHAP - Is the Challenge-Handshake Authentication Protocol as implemented by Microsoft (CHAP)? Microsoft's version of the PPTP protocol for VPNs is an authentication choice.

EAP - The Extensible Authentication Protocol (EAP) is a framework for authentication used in wireless networks and point-to-point interactions.

 

Final Words

With a free RADIUS Server, you don't have to worry about your private information getting out to people who don't need it, and you can easily control members' access levels. It can be added to your system with little effect on the rest of it.