Dhcp Relay Agent Configuration; Introduction To Dhcp Relay Agent; Application Environment; Fundamentals - 3Com Baseline 2928 PWR Plus User Manual

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DHCP Relay Agent Configuration

Introduction to DHCP Relay Agent

Application Environment

Since DHCP clients request IP addresses via broadcast messages, the DHCP server and clients must
be on the same subnet. Therefore, a DHCP server must be available on each subnet, which is not
practical.
DHCP relay agent solves the problem. Via a relay agent, DHCP clients communicate with a DHCP
server on another subnet to obtain configuration parameters. Thus, DHCP clients on different subnets
can contact the same DHCP server, and centralized management and cost reduction are achieved.

Fundamentals

Figure 2-1 shows a typical application of the DHCP relay agent.
Figure 2-1 DHCP relay agent application
DHCP client DHCP client
DHCP client
No matter whether a relay agent exists or not, the DHCP server and client interact with each other in a
similar way (see section
forwarding process on the DHCP relay agent.
DHCP relay agent
DHCP client
Dynamic IP Address Allocation
IP network
DHCP server
Process). The following describes the
2-1