Cisco Catalyst 3120 User Manual

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Cisco Catalyst Blade Switch 3120 for HP Software Configuration Guide
OL-12247-01
Chapter 9 Configuring IEEE 802.1x Port-Based Authentication
Understanding IEEE 802.1x Port-Based Authentication
Figure 9-3 Message Exchange
If IEEE 802.1x authentication times out while waiting for an EAPOL message exchange and MAC
authentication bypass is enabled, the switch can authorize the client when the switch detects an Ethernet
packet from the client. The switch uses the MAC address of the client as its identity and includes this
information in the RADIUS-access/request frame that is sent to the RADIUS server. After the server
sends the switch the RADIUS-access/accept frame (authorization is successful), the port becomes
authorized. If authorization fails and a guest VLAN is specified, the switch assigns the port to the guest
VLAN. If the switch detects an EAPOL packet while waiting for an Ethernet packet, the switch stops
the MAC authentication bypass process and stops IEEE 802.1x authentication.
Figure 9-4 shows the message exchange during MAC authentication bypass.
Figure 9-4 Message Exchange During MAC Authentication Bypass
201761
C
lient
Port Authorized
Port Unauthorized
EAPOL-Start
EAP-Request/Identity
EAP-Response/Identity
EAP-Request/OTP
EAP-Response/OTP
EAP-Success
RADIUS Access-Request
RADIUS Access-Challenge
RADIUS Access-Request
RADIUS Access-Accept
EAPOL-Logoff
Authentication
server
(RADIUS)
2
01762
C
lient
Switch
EAPOL Request/Identity
EAPOL Request/Identity
EAPOL Request/Identity
RADIUS Access/Request
RADIUS Access/Accept
Ethernet packet
Authentication
server
(RADIUS)

Cisco Catalyst 3120 Specifications

General

Brand	Cisco
Model	Catalyst 3120
Category	Switch
Language	English