Details
Controlling LAN access via 802.1x authentication can assist in preventing a malicious user from connecting an unauthorized PC to a switch port to inject or receive data from the network without detection.
Solution
Configure 802.1 x authentications on all host-facing access switch ports. To authenticate devices that do not support 802.1x, MAC Authentication Bypass must be configured.
Step 1: Configure the radius servers as shown in the example below:
SW1(config)#radius server RADIUS_1
SW1(config-radius-server)#address ipv4 10.1.22.3
SW1(config-radius-server)#key xxxxxx
SW1(config-radius-server)#exit
SW1(config)#radius server RADIUS_2
SW1(config-radius-server)#address ipv4 10.1.14.5
SW1(config-radius-server)#key xxxxxx
SW1(config-radius-server)#exit
Step 2: Enable 802.1x authentication on the switch:
SW1(config)#aaa new-model
SW1(config)#aaa group server radius RADIUS_SERVERS
SW1(config-sg-radius)#server name RADIUS_1
SW1(config-sg-radius)#server name RADIUS_2
SW1(config-sg-radius)#exit
SW1(config)#aaa authentication dot1x default group RADIUS_SERVERS
SW1(config)#dot1x system-auth-control
Step 3: Enable 802.1x on all host-facing interfaces as shown in the example below:
SW1(config)#int range g1/0 – 8
SW1(config-if-range)#switchport mode access
SW1(config-if-range)#authentication host-mode single-host
SW1(config-if-range)#dot1x pae authenticator
SW1(config-if-range)#authentication port-control auto
SW1(config-if-range)#end
Note: Single-host is the default. Host-mode multi-domain (for VoIP phone plus PC) or multi-auth (multiple PCs connected to a hub) can be configured as alternatives.
Supportive Information
The following resource is also helpful.
This security hardening control applies to the following category of controls within NIST 800-53: Identification and Authentication.This control applies to the following type of system Cisco.
References
- 800-53|IA-3
- CAT|I
- CCI|CCI-000778
- Rule-ID|SV-220623r539671_rule
- STIG-ID|CISC-L2-000020
- STIG-Legacy|SV-110217
- STIG-Legacy|V-101113
- Vuln-ID|V-220623