One of the most critical aspects of network device management is authentication, which ensures that only authorized users can access network resources. In this article, we will discuss how to implement RADIUS authentication using Windows Server NPS (Network Policy Server) for network device management.

RADIUS (Remote Authentication Dial-In User Service) is a networking protocol that provides centralized authentication, authorization, and accounting (AAA) management for users who connect and use a network service. RADIUS is commonly used for wireless networks, VPNs, and network device management.

The protocol works by authenticating users based on their credentials, which are typically a username and password, and then granting or denying access to the network device based on the user’s authorization level.

Windows Server NPS is a RADIUS server that provides authentication, authorization, and accounting services to network devices. It enables organizations to control access to network resources by providing a centralized authentication and authorization mechanism. NPS is a powerful tool that can help organizations enforce security policies, restrict access to sensitive data, and monitor network activity.

To implement RADIUS authentication using Windows Server NPS for network device management, follow these steps:

Install and configure NPS: Install NPS on a Windows Server, and configure it to use RADIUS as the authentication protocol. You can use the NPS wizard to set up RADIUS authentication.

Configure network devices to use RADIUS: Configure your network devices to use RADIUS as the authentication protocol. You will need to provide the IP address of the NPS server, the shared secret, and the RADIUS port number.

Create network policies: In NPS, create network policies that define the conditions under which a user is granted access to the network device. Network policies are a set of rules that define who can access the network device, under what circumstances, and what level of access they have.

Configure authentication methods: Configure the authentication methods that NPS will use to authenticate users. You can use different authentication methods, such as EAP-TLS, PEAP-MSCHAPv2, or EAP-TTLS, depending on your security requirements.

Test the configuration: Test the RADIUS authentication configuration by attempting to access the network device. Verify that you can successfully authenticate, and that you are granted access according to your authorization level.

Implementing RADIUS authentication using Windows Server NPS for network device management provides several benefits. It provides a centralized authentication and authorization mechanism, making it easier to manage user access to network resources. It also enables organizations to enforce security policies, restrict access to sensitive data, and monitor network activity.

In conclusion, implementing RADIUS authentication using Windows Server NPS is an effective way to manage network devices securely. By following the steps outlined in this article, you can set up a robust authentication and authorization mechanism that can help protect your organization’s network resources from unauthorized access.

Create NPS using PowerShell cmdlets and enable RADIUS authentication on Cisco devices:

Creating NPS using PowerShell cmdlets:

Open PowerShell as an administrator.
Install the NPS module by running the following command:

Install-WindowsFeature NPAS-Policy-Server

Create a new NPS server by running the following command:

New-NpsRadiusServer -Name "NPS_Server_Name" -Address "NPS_Server_IP_Address" -AuthenticationPort 1812 -SharedSecret "NPS_Server_Shared_Secret"

Create a new NPS network policy by running the following command:

New-NpsNetworkPolicy -Name "Policy_Name" -TunnelType "VLAN" -EapTls -Enabled -Conditions @{UserGroups="Domain Users"} -AuthenticationMethods @{Eap="EapTls"}

Add the NPS server to Active Directory by running the following command:

 Add-Computer -DomainName "domain.com" -Credential "domain\admin" -Restart 

Enabling RADIUS authentication on Cisco devices:

Log in to the Cisco device using a console or SSH session.
Enter configuration mode by running the following command: enable

Configure the device to use RADIUS authentication by running the following command:

aaa new-model

Configure the RADIUS server by running the following command:

radius-server host "NPS_Server_IP_Address" auth-port 1812 key "NPS_Server_Shared_Secret"

Enable RADIUS authentication on the desired interfaces by running the following command:

interface "interface_name", followed by the command authentication login radius

By following these steps, you can create an NPS server using PowerShell cmdlets and enable RADIUS authentication on Cisco devices.

This provides a secure authentication and authorization mechanism for managing network devices.

Follow another guide I wrote sometime ago;
Network Device Management with RADIUS Authentication using Windows NPS

In this article, we will explore the basics of NAC, including how it works, why it is important, and the key components of a NAC solution.

What is Network Access Control (NAC)?

Network Access Control (NAC) is a security solution that enables organizations to control access to their networks. It provides a way to authenticate users and devices, enforce access policies, and monitor network activity to identify potential security threats.

NAC solutions use a range of techniques to ensure that only authorized users and devices can access the network. These include identity and access management, endpoint compliance checks, and policy enforcement.

How Does NAC Work?

NAC solutions typically include several key components, including:

Endpoint Identification: NAC solutions use various techniques to identify the devices that are attempting to access the network, such as MAC addresses, IP addresses, and user credentials.

Authentication and Authorization: Once an endpoint is identified, the NAC solution will authenticate the user and/or device and verify that it is authorized to access the network.

Policy Enforcement: NAC solutions enforce access policies to ensure that only authorized users and devices can access the network. Policies can be based on a range of factors, such as user identity, device type, and location.

Endpoint Compliance: NAC solutions also check endpoints for compliance with security policies, such as the presence of antivirus software or the latest operating system patches.

Monitoring and Reporting: NAC solutions monitor network activity to detect potential security threats, such as unauthorized access attempts or suspicious network activity.

Why is NAC Important?

Network Access Control (NAC) is critical for maintaining the security and integrity of your network. By controlling access to your network resources, you can prevent unauthorized access and protect sensitive data from theft or loss.

NAC solutions also provide a way to enforce security policies and ensure that all devices on your network are up-to-date with the latest security patches and antivirus software. This reduces the risk of malware infections and other security threats that could compromise your network.

Cisco provides various commands and tools that can be used for Network Access Control (NAC) solutions, endpoint compliance, policy enforcement, network security, authentication and authorization, and identity and access management. Some of the common commands and tools include:

Cisco Identity Services Engine (ISE): This is a comprehensive NAC solution that provides identity and access management, policy enforcement, and endpoint compliance features. It can be managed using various CLI (Command Line Interface) commands, such as “show” commands to display configuration details and “configure” commands to modify the configuration.

Cisco TrustSec: This is a network security solution that provides secure segmentation and policy-based access control. It can be configured using various CLI commands, such as “device-tracking” to enable device tracking and “policy” commands to configure access policies.

Cisco Secure Access Control System (ACS): This is a centralized access control solution that provides authentication and authorization for network devices and users. It can be managed using various CLI commands, such as “aaa” commands to configure authentication, authorization, and accounting policies.

Cisco AnyConnect: This is a VPN solution that provides secure remote access to network resources. It can be configured using various CLI commands, such as “vpn” commands to configure VPN policies and “webvpn” commands to configure web-based VPN access.

Cisco Adaptive Security Appliance (ASA): This is a firewall solution that provides network security and access control. It can be managed using various CLI commands, such as “access-list” commands to configure access control lists and “vpn-filter” commands to configure VPN access policies.

Overall, Cisco provides a wide range of CLI commands and tools that can be used to configure and manage NAC solutions, endpoint compliance, policy enforcement, network security, authentication and authorization, and identity and access management.

Conclusion

Network Access Control (NAC) is a critical component of network security, designed to prevent unauthorized access to your network resources. NAC solutions provide a range of features, including identity and access management, policy enforcement, and endpoint compliance checks, to ensure that only authorized users and devices can access your network.

By implementing a NAC solution, you can reduce the risk of security threats, protect sensitive data, and ensure the integrity of your network. So if you haven’t already implemented NAC in your organization, now is the time to do so.