About Unicast Reverse Path Forwarding - Cisco Catalyst 4500 Series Configuration Manual

Configuring Unicast Reverse Path Forwarding
This chapter describes the Unicast Reverse Path Forwarding (Unicast RPF) feature. The Unicast RPF
feature helps to mitigate problems that are caused by malformed or forged IP source addresses that are
passing through a switch.
For a complete description of the Unicast RPF commands in this chapter, refer to the chapter "Unicast
Reverse Path Forwarding Commands" of the Cisco IOS Security Command Reference. To locate
documentation of other commands that appear in this chapter, use the command reference master index
or search online.
To identify the hardware platform or software image information associated with a feature, use the
Feature Navigator on Cisco.com to search for information about the feature or refer to the software
release notes for a specific release. For more information, see the "Identifying Supported Platforms"
section in the chapter "Using Cisco IOS Software."
This chapter includes the following sections:
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Note For complete syntax and usage information for the switch commands used in this chapter, first look at
the Cisco Catalyst 4500 Series Switch Command Reference and related publications at this location:
http://www.cisco.com/en/US/products//hw/switches/ps4324/index.html
If the command is not found in the Catalyst 4500 Series Switch Command Reference, it will be found in
the larger Cisco IOS library. Refer to the Cisco IOS Command Reference and related publications at this
location:
http://www.cisco.com/en/US/products/ps6350/index.html

About Unicast Reverse Path Forwarding

The Unicast RPF feature helps to mitigate problems that are caused by the introduction of malformed or
forged (spoofed) IP source addresses into a network by discarding IP packets that lack a verifiable IP
source address. For example, a number of common types of denial-of-service (DoS) attacks, including
OL-25340-01
About Unicast Reverse Path Forwarding, page 34-1
Unicast RPF Configuration Tasks, page 34-9
Monitoring and Maintaining Unicast RPF, page 34-11
Unicast RPF Configuration Example: Inbound and Outbound Filters, page 34-12
C H A P T E R
Software Configuration Guide—Release IOS XE 3.3.0SG and IOS 15.1(1)SG
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