CHAPTER
23-1
Software Configuration Guide—Release 12.2(25)SG
OL-7659-03
23
Configuring Cisco Express Forwarding
This chapter describes Cisco Express Forwarding (CEF) on the Catalyst 4500 series switch. It also
provides guidelines, procedures, and examples to configure t his feature.
This chapter includes the following major sections:
Overview of CEF, page 23-1
Catalyst 4500 Series Switch Implementation of CEF, page 23-3
CEF Configuration Restrictions, page 23-6
Configuring CEF, page 23-6
Monitoring and Maintaining CEF, page 23-8
Note For complete syntax and usage information for the switch commands used in this chapter, refer to the
Catalyst 4500 Series Switch Cisco IOS Command Reference and related publications at
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/index.htm.

Overview of CEF

This section contains information on the two primary components that comprise the CEF operation:
Benefits of CEF, page 23-1
Forwarding Information Base, page 23-2
Adjacency Tables, page 23-2

Benefits of CEF

CEF is advanced Layer 3 IP switching technology that optimizes performance and scalability for large
networks with dynamic traffic patterns or networks with intensive web-based applic ations and
interactive sessions.