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Cisco IE 2000 Switch Software Configuration Guide
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Configuring DHCP
Finding Feature Information
Your software release may not support all the features documented in this chapter. For the latest feature
information and caveats, see the release notes for your platform and software release.
Use Cisco Feature Navigator to find information about platform support an d Cisco software image
support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on
Cisco.com is not required.

Information About Configuring DHCP

This chapter describes how to configure Dynamic Host Configuration Protocol (DHCP) snooping and
option-82 data insertion, and the DHCP server port-based address allocation features on the switch. It
also describes how to configure the IP source guard feature.

DHCP Snooping

DHCP is widely used in LAN environments to dynamically assign host IP addresses from a centralized
server, which significantly reduces the overhead of administration of IP addresses. DHCP also helps
conserve the limited IP address space because IP addresses no longer need to be permanently assigned
to hosts; only those hosts that are connected to the network consume IP addresses.

DHCP Server

The DHCP server assigns IP addresses from specified address pools on a switch or router to DHCP
clients and manages them. If the DHCP server cannot give the DHCP client the requested configuration
parameters from its database, it forwards the request to one or more seco ndary DHCP servers defined by
the network administrator.