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Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
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Chapter 9      Configuring IEEE 802.1x Port-Based Authentication
    Understanding IEEE 802.1x Port-Based Authentication
• Using IEEE 802.1x with Port Security, page 9-7
• Using IEEE 802.1x with Voice VLAN Ports, page 9-8
• Using IEEE 802.1x with VLAN Assignment, page 9-8
• Using IEEE 802.1x with Guest VLAN, page 9-9
• Using IEEE 802.1x with Wake-on-LAN, page 9-10
Device Roles
With IEEE 802.1x port-based authentication, the devices in the network have specific roles as shown in 
Figure 9-1.
Figure 9-1 IEEE 802.1x Device Roles
•
Client—the device (workstation) that requests access to the LAN and switch services and responds 
to requests from the switch.The workstation must be running IEEE 802.1x-compliant client software 
such as that offered in the Microsoft Windows XP operating system. (The client is the supplicant in 
the IEEE 802.1x specification.)
Note To resolve Windows XP network connectivity and IEEE 802.1x authentication issues, read 
the Microsoft Knowledge Base article at this URL: 
http://support.microsoft.com/support/kb/articles/Q303/5/97.ASP
• Authentication server—performs the actual authentication of the client. The authentication server 
validates the identity of the client and notifies the switch whether or not the client is authorized to 
access the LAN and switch services. Because the switch acts as the proxy, the authentication service 
is transparent to the client. In this release, the RADIUS security system with Extensible 
Authentication Protocol (EAP) extensions is the only supported authentication server. It is available 
in Cisco Secure Access Control Server Version 3.0 or later. RADIUS operates in a client/server 
model in which secure authentication information is exchanged between the RADIUS server and 
one or more RADIUS clients.
• Switch (edge switch or wireless access point)—controls the physical access to the network based on 
the authentication status of the client. The switch acts as an intermediary (proxy) between the client 
and the authentication server, requesting identity information from the client, verifying that 
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Workstations
(clients)
Authentication
server
(RADIUS)