Configuring Port and System Security 481
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Configuring Port and System 
Security
This chapter describes how to configure port-based security features, which 
control access to the network through the switch ports, and the denial of 
service (DoS) feature. 
Port-based security includes IEEE 802.1X authentication and port MAC 
locking.
• IEEE 802.1X provides an authentication mechanism to devices connected 
to the switch. Network access is permitted only to authorized devices 
(clients).
• Port MAC locking is used to enable security on a per-port basis. When a 
port is locked, only packets with allowable source MAC addresses can be 
forwarded. All other packets are discarded. Port-MAC locking allows a 
configurable limit to the number of source MAC addresses that can be 
learned on a port.
The topics covered in this chapter include:
• IEEE 802.1X
• Port Security (Port-MAC Locking)
• Denial of Service
NOTE: Port-based security can also be accomplished by using Access Control 
Lists (ACLs). For information about configuring ACLs, see "Configuring Access 
Control Lists" on page 523.