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DHCP overview 
The Dynamic Host Configuration Protocol (DHCP) provides a framework to assign configuration 
information to network devices. 
Figure 15 sho
ws a typical DHCP application scenario where the DHCP clients and the DHCP server 
reside on the same subnet. The DHCP clients can also obtain configuration parameters from a 
DHCP server on another subnet through a DHCP relay agent. For more information about the DHCP 
relay agent, see "Configuring the DHCP relay agent."
 
Figure 15 A typical DHCP application 
 
 
DHCP address allocation 
Allocation mechanisms 
DHCP supports the following allocation mechanisms: 
• Static allocation—The network administrator assigns an IP address to a client, such as a 
WWW server, and DHCP conveys the assigned address to the client. 
• Automatic allocation—DHCP assigns a permanent IP address to a client. 
• Dynamic allocation—DHCP assigns an IP address to a client for a limited period of time, 
which is called a lease. Most DHCP clients obtain their addresses in this way.