Cisco Systems C819HG4GVK9 manual Configuring MAC Table Manipulation, Port Security, 10-9, Command

Chapter 10 Configuring the Ethernet Switches

How to Configure Ethernet Switches

Configuring MAC Table Manipulation

For information on how to configure MAC table manipulation, see Configuring MAC Table

Manipulation.

Port Security

The topic of enabling known MAC address traffic deals with port security. Port security can be either static or dynamic.

Static port security allows the user to specify which devices are allowed access through a given switch port. The specification is done manually by placing allowed device MAC addresses in the MAC address table. Static port security is also known as MAC address filtering.

Dynamic port security is similar. However, instead of specifying the MAC address of the devices, the user specifies the maximum number of devices that will be allowed on the port. If the maximum number specified is more than the number of MAC addresses specified manually, the switch will learn the MAC address automatically, up to the maximum specified. If the maximum number specified is less than the number of MAC addresess already specified statically, an error message will be produced.

The following command is used to specify static or dynamic port security.

Command	Purpose
Router(config)# mac-address-table secure	<mac-address>enables static port security. Use
[<mac-address> maximum maximum addresses]	of the keyword maximum enables dynamic port
fastethernet interface-id [vlan <vlan id>]	security.

Configuring Cisco Discovery Protocol

For information on how to configure Cisco Discovery Protocol (CDP), see Configuring Cisco Discovery Protocol.

This section contains information on the following topics:

•Enabling CDP

•Enabling CDP on an interface

•Monitoring and maintaining CDP

	Cisco 819 Series Integrated Services Routers Software Configuration Guide
OL-23590-02		10-9