Switchport Protected - Cisco Catalyst 3550 Command Reference Manual

Chapter 2 Cisco IOS Commands

switchport protected

Use the switchport protected interface configuration command to isolate unicast, multicast, and
broadcast traffic at Layer 2 from other protected ports on the same switch. Use the no form of this
command to disable protection on the port.
Syntax Description
This command has no arguments or keywords.
Defaults
No protected port is defined. All ports are nonprotected.
Command Modes
Interface configuration
Command History Release
12.1(4)EA1
Usage Guidelines
The switchport protection feature is local to the switch; communication between protected ports on the
same switch is possible only through a Layer 3 device. To prevent communication between protected
ports on different switches, you must configure the protected ports for unique VLANs on each switch
and configure a trunk link between the switches. A protected port is different from a secure port.
A protected port does not forward any unicast, multicast, or broadcast traffic to any other protected port.
A protected port continues to forward unicast, multicast, and broadcast traffic to unprotected ports and
vice versa.
Port monitoring does not work if both the monitor and monitored ports are protected ports.
Protected ports are supported on 802.1Q trunks.
Examples
This example shows how to enable a protected port on an interface:
Switch(config)# interface gigabitethernet0/3
Switch(config-if)# switchport protected
You can verify your settings by entering the show interfaces interface-id switchport privileged EXEC
command.
Related Commands Command
show interfaces
switchport
switchport block
78-11195-09
switchport protected
no switchport protected
Modification
This command was first introduced.
Description
Displays the administrative and operational status of a switching (nonrouting)
port, including port blocking and port protection settings.
Prevents unknown multicast or unicast traffic on the interface.
Catalyst 3550 Multilayer Switch Command Reference
switchport protected
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