Description:

If an access point is installed in a publicly accessible area (e.g. at a school or hotel), we recommend that you use RADIUS authentication to ensure that a client (e.g. a notebook PC) is unable to gain access to the management network even if it is connected by cable to the Ethernet socket that is intended for use by the access point.

This article describes how RADIUS authentication is set up for an access point with LCOS LX so that only this has access to the management network.

Access points that are operated in a WLAN-Controller scenario must each be configured individually. A central configuration of the steps described here via a WLAN-Controller is not possible.

This scenario can also be implemented with LCOS access points.



Requirements:

  • LANCOM router as the RADIUS server
  • Access point with LCOS LX operating system
  • One of the following LANCOM switch models:
    • GS-24xx 
    • GS-3xxx
    • XS-3xxx 
  • LCOS as of version 10.30 on the router which acts as RADIUS server (download latest version)
  • LCOS LX as of version 5.20 RU2 (download latest version)
  • LCOS SX as of version 4.00 for GS-3xxx (download latest version)
  • LCOS SX as of version 4.30 for GS-24xx / XS-3xxx (download latest version)
  • LANtools as of version 10.30 (download latest version), 10.40 RU1 when configuring the access point via LANconfig 
  • Any web browser for accessing the web interface of the GS-3xxx and the access point


Scenario:

  • A LANCOM router with the IP address 192.168.1.254 is operating as a RADIUS server.
  • A switch of the GS-3xxx series with the IP address 192.168.1.250 is operating as a RADIUS authenticator. The switch therefore forwards the requests from the access point to the RADIUS server.
  • An access point with the LCOS LX operating system presents its authorization credentials and logs on to the switch, thus acting as the RADIUS supplicant.
  • After a successful login to the RADIUS server, the switch should enable communication on the port that the access point is connected to.

Diagram showing the configuration of a network, featuring a LANCOM router connected to a RADIUS server, a GSxxx switch, and an Access Point with LCOS LX, all identified by IP addresses and roles like RADIUS authenticator and supplicant.


Procedure:

1) Configuring the RADIUS server on the LANCOM router:

1.1) In LANconfig, open the configuration for the router, navigate to the menu RADIUS → Server and set a checkmark next to RADIUS authentication active.

Image displaying a complex configuration interface for network settings, including active RADIUS and RADSEC services, accounting settings, and user database management options.

1.2) Navigate to the menu RADIUS services ports.

Screenshot of a technical configuration interface displaying settings for RADIUS authentication, RADSEC, accounting, and server access, alongside options for network routing, firewall, QoS, and certificate management.

1.3) Check that the authentication port is set to 1812.

Screenshot of a user interface displaying options including RADIUS service, sports, accounting, and port configuration settings.

1.4) Go to the menu IPv4 clients.

Screenshot of a network configuration interface displaying settings for RADIUS authentication, RADSEC, and accounting services, with options for defining ports, managing certificates, and configuring user details for server authentication.

1.5) Create a new entry and enter the following parameters:

  • IP address: Enter the switch IP address so that this can authenticate itself as the RADIUS authenticator at the RADIUS server.
  • Netmask: Enter the netmask 255.255.255.255. This stands for a single IP address.
  • Protocols: Check that the protocol is set to RADIUS.
  • Client secret : Enter a password that the switch uses to authenticate itself at the RADIUS server . This is entered on the switch in step 2.1 .

Screenshot of a technical configuration interface displaying options for a new client entry, protocols, and password settings.

1.6) Go to the menu User table.

A screenshot of a network configuration interface showing various settings including FZI RADIUS authentication, RADSEC status, RADIUS accounting, and user database options among other network protocols and security configurations.

1.7) Create a new entry and adjust the following parameters:

  • Name / MAC address: Enter a user name that the access point uses to authenticate itself at the RADIUS server.
  • Password: Enter a password that the access point uses to authenticate itself at the RADIUS server.
  • Service type: From the drop-down menu, select Call check.
  • Expiry type: From the drop-down menu, select Never so that the user account remains permanently valid.

As of SWOS 4.00 RU2 the switch sends RADIUS requests with the Service type Call check. In this case the Service type in this menu als has to be set to Call check. As an alternative the option Any can also be selected.

As of LCOS SX 4.00 RU5 the Service type Framed is used for RADIUS requests and the Service type Call-Check is used for MAC-based requests. In this case the Service type has to be set to Framed. As an alternative the option Any can also be selected.

The Service type Call check is supported as of LCOS 10.30.

Screenshot of a technical configuration interface displaying options for user entry, password generation, access restrictions, and other network settings.

1.8) This concludes the configuration of the RADIUS server on the LANCOM router. You can now write the configuration back to the device.



2) Configuring the RADIUS authenticator on the switch:

2.1) Open the webinterface of the device, switch to the menu Security → RADIUS → Configuration and click Add New Server.

Image of a RADIUS server configuration interface showing options for global settings, timeout, retransmit, dead time, keys, NAS IP details, and server-specific settings such as hostname, auth port, and acct port.

2.2) Modify the following parameters in the Server Configuration and click Apply:

  • Hostname: Enter the IP address of the router that was set up as the RADIUS server in step 1.
  • KeyEnter the Client secret set in step 1.5. The switch uses this password to authenticate itself at the RADIUS server.

Screenshot of a server configuration interface showing options to delete, set hostname, authentication port, accounting port, timeout, retransmit, and keys, with apply and reset buttons visible.

2.3) Go to the menu Security → 802.1X → Configuration and activate the 802.1X authentication by setting the slider Mode to on.

Screenshot of a system configuration menu displaying settings for network reauthentication, EAPOL settings, aging and hold times, and RADIUS-assigned features for quality of service and VLAN management.

2.4) In the Port Configuration select the Admin State Port-based 802.1X in the dropdown menu for the port that the access point will be connected to. Click Apply afterwards.

With the option Port-based 802.1X, solely the access point should be able to authenticate itself. All other end devices connected via WLAN can communicate via the switch port without authentication. For this reason it is important to provide the WLAN end devices with their own network that is separated from the management network by VLAN. You can use this Knowledge Base article to help you here.


Image depicting a configuration menu for network port settings showing options like PortAdminState, VLAN assignments, QoS settings, and controls for RADIUS authentication protocols.

Image showcasing a technical configuration menu with options labeled as 'Authorized', 'Force Authorized', 'Disabled', 'Reauthenticate', and 'Reinitialize'.

2.5) Click the red disk symbol on the upper right side to save the configuration as Start configuration

The Start configuration is boot persistent and is therefore available even after a restart or a power failure.

Close-up view of a technical user interface displaying the code 'GSSxP'.

2.6) This concludes the configuration of the switch.



3) Configuring the RADIUS supplicant on the access point:

3.1) Configuring the RADIUS supplicant via LANconfig:

3.1.1) Open the configuration for the access point in LANconfig and switch to the menu item Management → 802.1X-supplicant → Configure 802.1X supplicant.

The image displays a configuration menu for authenticating a device to a network, listing various settings including general admin, UMC, PyXSupplicant, software update, date and time, and wireless LAN.

3.1.2) Edit the entry INTRANET.

Screenshot of a user interface displaying the configuration options for Xsupplicant, including partially visible, undefined settings.

3.1.3) Modify the following parameters:

  • Method: From the drop-down menu, select MD5. MD5 is used as the standard method in LANCOM routers.
  • Username: Enter the Name / MAC address set in step 1.7. The access point uses this to authenticate itself at the RADIUS server.
  • Password: Enter the password set in step 1.7. The access point uses this to authenticate itself at the RADIUS server.

An image showing a configuration menu for Xsupplicant with options to edit the entry including interface name, method, and password fields.

3.1.4) The configuration of the access point via LANconfig is now complete. You can now write the configuration back to the device.


3.2) Configuring the RADIUS supplicant via WEBconfig:

3.2.1) Connect to the access point via WEBconfig and switch to the menu System configuration → Adjust the network settings of this device.

A screenshot of a technical configuration dashboard displaying network settings, including Wi-Fi configuration, DHCP settings, Pv modes, and addresses with an option for IXSupplicant.

3.2.2) For the 802.1X supplicant, adjust the following parameters and then click on Confirm:

  • Username: Enter the Name / MAC address set in step 1.7. The access point uses this to authenticate itself at the RADIUS server.
  • Password: Enter the password set in step 1.7. The access point uses this to authenticate itself at the RADIUS server.
  • Method: From the drop-down menu, select MD5MD5 is used as the standard method in LANCOM routers.

The image displays a screen showing network settings, featuring fields for IPv6 addresses, primary and secondary DNS, gateway, username, password, and configuration methods.

3.2.3) The configuration of the access point is now complete.