From Perimeter L3 Switch Security Technical Implementation Guide - Cisco
Part of NET-NAC-009
The IEEE 802.1x standard is a client-server based access control and authentication protocol that restricts unauthorized clients from connecting to a local area network through host facing switch ports. The authentication server authenticates each client connected to to a switch port before making any services available to the client from the LAN. Unless the client is successfully authenticated, 802.1x access control allows only Extensible Authentication Protocol over LAN (EAPOL) traffic through the port to which the client is connected. After authentication is successful, normal traffic can pass through the port. Without the use of 802.1x, a malicious user could use the switch port to connect an unauthorized piece of computer or other network device to inject or steal data from the network without detection.
Verify if the switch configuration has 802.1x authentication implemented for all access switch ports connecting to LAN outlets (i.e. RJ-45 wall plates) or devices not located in the telecom room, wiring closets, or equipment rooms. If 802.1x authentication is not configured on these host-facing access switch ports, this is a CAT 1 finding. If MAC address filtering is implemented in lieu of 802.1x authentication, this finding will be downgraded to a CAT 3. Verify 802.1x authentication is enabled on the switch and host facing switch ports: Step 1: Verify that an 802.1x authentication server has been configured similar to the following example: Switch(config)# radius-server host x.x.x.x auth-port 1813 key !R4d1u$K3y! Switch(config)# aaa new-model Switch(config)# aaa authentication dot1x default group radius Step 2: Verify 802.1x authentication has been enabled globally on the network device similar to the following example: Switch(config)# dot1x system-auth-control Step 3: Verify that all host-facing access switchports are configured to use 802.1x similar to the examples below: Switch(config)# interface fastethernet0/2 Switch(config-if)# switchport mode access Switch(config-if)# switchport port-security Switch(config-if)# dot1x port-control auto OR Switch(config)# interface fastethernet0/2 Switch(config-if)# switchport mode access Switch(config-if)# switchport port-security Switch(config-if)# authentication port-control auto If 802.1x is not being used, determine if MAC filtering is used on each host-facing access switch port as shown in the following example: Switch(config)# interface fastethernet0/3 Switch(config-if)# switchport mode access Switch(config-if)# switchport port-security Switch(config-if)# switchport port-security maximum 1 Switch(config-if)# switchport port-security mac-address 1000.2000.3000 NOTE: The section below is intended for classified networks. If it’s determined that 802.1x is not implemented on a classified network, the Traditional review team must be notified to determine if the physical requirements are implemented. For a site to be downgraded to a CAT III open finding, the physical security requirements must be implemented in addition to static MAC or sticky secure MAC port security. If both physical and logical downgrades are not implemented, a CAT I open finding will be issued. If classified LAN drops are not authenticated by an 802.1x implementation, they must be located within spaces properly established as Secret vaults, Secret Secure Rooms (AKA: Collateral Classified Open Storage Areas), TS secure room, or SCIF. Otherwise, one of the following supplemental physical security controls must be implemented. 1. Wall jacks must be secured when unattended by persons with Secret or higher clearance with a properly constructed lock box (Hoffman or similar commercial product or locally fabricated). The lock box must have no exposed or removable hinges. The hasp hardware must be riveted to the box or otherwise installed so that removal will require physical breaking of the box; thereby leaving evidence of actual or attempted entry. The lock box must be secured with a 3-position high security combination padlock (IAW the NSTISSI 7003). The S&G 8077 combination padlock is the only existing padlock meeting this standard. 2. If lock boxes are not used, the alternative is to physically disconnect the SIPRNet link at the SIPRNet point of presence (PoP) after normal duty hours. The PoP must be located within a proper Secret or higher secure room.
Configure 802.1x authentication on all host facing access switch ports.
Lavender hyperlinks in small type off to the right (of CSS
class id
, if you view the page source) point to
globally unique URIs for each document and item. Copy the
link location and paste anywhere you need to talk
unambiguously about these things.
You can obtain data about documents and items in other
formats. Simply provide an HTTP header Accept:
text/turtle
or
Accept: application/rdf+xml
.
Powered by sagemincer