Cisco me 3400 Guia Do Programa

This chapter describes how to configure DHCP snooping and option-82 data insertion, and the DHCP 
server port-based address allocation features on the Cisco ME 3400 Ethernet Access switch. It also 
describes how to configure the IP source guard feature. 

For complete syntax and usage information for the commands used in this chapter, see the command 
reference for this release, and see the “DHCP Commands” section in the Cisco IOS IP Command 
Reference, Volume 1 of 3: Addressing and Services, Release 12.2. 

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.