Cisco WS-SUP32-GE-3B Software Configuration Guide - Page 713

42 C H A P T E R Configuring IEEE 802.1X Port-Based Authentication This chapter describes how to configure IEEE 802.1X port-based authentication to prevent unauthorized devices (clients) from gaining access to the network. Note For complete syntax and usage information for the commands used in this chapter, refer to the Catalyst Supervisor Engine 32 PISA Cisco IOS Command Reference, Release 12.2ZY, at this URL: http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.2ZY/command/reference/cmdref.h tml This chapter consists of these sections: • Understanding 802.1X Port-Based Authentication, page 42-1 • Default 802.1X Port-Based Authentication Configuration, page 42-5 • 802.1X Port-Based Authentication Guidelines and Restrictions, page 42-6 • Configuring 802.1X Port-Based Authentication, page 42-7 • Displaying 802.1X Status, page 42-15 Understanding 802.1X Port-Based Authentication The IEEE 802.1X standard defines a client-server-based access control and authentication protocol that restricts unauthorized clients from connecting to a LAN through publicly accessible ports. The authentication server authenticates each client connected to a switch port and assigns the port to a VLAN before making available any services offered by the switch or the LAN. Until the client is 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. These sections describe IEEE 802.1X port-based authentication: • Device Roles, page 42-2 • Authentication Initiation and Message Exchange, page 42-3 • Ports in Authorized and Unauthorized States, page 42-4 • Supported Topologies, page 42-4 OL-11439-03 Catalyst Supervisor Engine 32 PISA Cisco IOS Software Configuration Guide, Release 12.2ZY 42-1