Dhcp Overview; Introduction To Dhcp; Dhcp Ip Address Assignment - 3Com 4210 PWR Configuration Manual

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Introduction to DHCP

DHCP IP Address
Assignment
IP Address Assignment
Policy
DHCP O
VERVIEW
With networks getting larger in size and more complicated in structure, lack of
available IP addresses becomes the common situation the network administrators
have to face, and network configuration becomes a tough task for the network
administrators. With the emerging of wireless networks and the using of laptops,
the position change of hosts and frequent change of IP addresses also require new
technology. Dynamic host configuration protocol (DHCP) is developed to solve
these issues.
DHCP adopts a client/server model, where the DHCP clients send requests to
DHCP servers for configuration parameters; and the DHCP servers return the
corresponding configuration information such as IP addresses to implement
dynamic allocation of network resources.
A typical DHCP application includes one DHCP server and multiple clients (such as
PCs and laptops), as shown in Figure 85.
Figure 85 Typical DHCP application
DHCP client DHCP client
DHCP client
Currently, DHCP provides the following three IP address assignment policies to
meet the requirements of different clients:
Manual assignment. The administrator configures static IP-to-MAC bindings for
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some special clients, such as a WWW server. Then the DHCP server assigns
these fixed IP addresses to the clients.
Automatic assignment. The DHCP server assigns IP addresses to DHCP clients.
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The IP addresses will be occupied by the DHCP clients permanently.
DHCP server
DHCP client