Authenticating an IP phone using 802.1X

This use case shows the configuration required on a RUCKUS ICX device to authenticate an 802.1X-capable phone in a voice VLAN. In the following example, after authentication, the phone will be authenticated in voice VLAN 200.

RADIUS configuration

Create a profile for the phone on the RADIUS server, and configure the attributes in the following table.

RUCKUS ICX switch configuration

1. Specify RADIUS as an authentication server. The following command configures the switch to use the configured RADIUS server to authenticate 802.1X authentication or MAC authentication clients.

   device(config)# aaa authentication dot1x default radius

2. Configure a RADIUS server. In the following example, the RADIUS server IP address is 10.20.64.208 and the shared key is "secret". The shared key must match the key given during client configuration on the RADIUS server. UDP port 1812 is used for RADIUS authentication messages, and UDP port 1813 is used for RADIUS accounting messages.

   device(config)# radius-server host 10.20.64.208 auth-port 1812 acct-port 1813 default key secret dot1x mac-auth web-auth

3. Create a VLAN to use as the auth-default VLAN. This VLAN must be configured to enable authentication. When any port is enabled for 802.1X authentication or MAC authentication, the port is moved into this VLAN by default as a MAC VLAN member. Sometimes the RADIUS server may authenticate the client but not return VLAN information on where the client should be placed. The auth-default VLAN is used in this scenario.

   device(config)# vlan 2 name auth-default-vlan
   device(config-vlan-2)# exit

4. The authentication-enabled port must be a tagged member of the voice VLAN before configuring LLDP. The virtual interface IP address of the voice VLAN will be used as the gateway IP address for the phone. In this example, VLAN 200 is used as the voice VLAN.

   device(config)# vlan 200 name voice
   device(config-vlan-200)# tagged ethernet 1/1/1
   device(config-vlan-200)# router-interface ve 200
   device(config-vlan-200)# exit
   device(config)# interface ve 200
   device(config-vif-200)# ip address 172.20.74.1/24
   

5. Configure the IP helper on the virtual interface of the voice VLAN so that a DHCP request from the IP phone is forwarded to the call manager. In the following steps, the call manager IP address is 10.20.74.31.

   device(config-vif-200)# ip helper-address 1 10.20.74.31
   device(config-vif-200)# exit
   

6. LLDP will be configured automatically if the Foundry-Voice-Phone-Config attribute is configured in the RADIUS server. LLDP advertises the VLAN information so that the client connected to the port learns the voice VLAN.

   If the Foundry-Voice-Phone-Config attribute is not configured, configure LLDP manually to advertise VLAN 200 as the voice VLAN on port 1/1/11. An LLDP warning message will be shown to indicate that port 1/1/11 is not part of VLAN 200. This warning can be ignored because port 1/1/11 will be added to VLAN 200 by way of dynamic VLAN assignment after authentication.

   device(config)# lldp run
   device(config)# lldp med network-policy application voice tagged vlan 200 priority 5 dscp 46 ports ethernet 1/1/11
   LLDP Warning: Network policy: Port 1/1/11 is not a member of VLAN 200
   

7. Specify which VLAN ID to use as the auth-default VLAN under authentication mode. Refer to Step 3 for the use of the auth-default VLAN.

   device(config)# authentication
   device(config-authen)# auth-default-vlan 2

8. Enable 802.1X on the switch under authentication mode, and enable 802.1X on port 1/1/11. Configure the port control mode as auto in general configuration mode. This mode enables 802.1X authentication on the interface.

   device(config)# authentication
   device(config-authen)# dot1x enable
   device(config-authen)# dot1x enable ethernet 1/1/11
   device(config-authen)# exit
   device(config)# dot1x port-control auto ethernet 1/1/11 
   

9. Enable PoE on port 1/1/11 using the inline power command in interface configuration mode.

   device(config)# interface ethernet 1/1/11
   device(config-if-e1000-1/1/11)# inline power
   device(config-if-e1000-1/1/11)# exit
   

10. To verify the authentication-related configuration on the switch, use the show run authentication command. Authentication-related configurations are stored under the keyword "authentication".

    device# show run authentication
    authentication
     critical-vlan 601
     auth-default-vlan 2
     restricted-vlan 401
     auth-fail-action restricted-vlan
     re-authentication
     dot1x enable
     dot1x enable ethe 1/1/11  
     dot1x guest-vlan 501
    !