H3C Technologies H3C S3100 Series Switches - Manual (Page 354)

Operation Manual – DLDP
H3C S3100-52P Ethernet Switch Chapter 1 DHCP Overview
1-1
Chapter 1 DHCP Overview
1.1 Introduction to DHCP
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 in this background.
DHCP adopts a client/server model, where DHCP clients send requests to DHCP
servers for configuration parameters; and the DHCP servers return the corresponding
configuration information such as IP addresses to configure IP addresses dynamically.
A typical DHCP application includes one DHCP server and multiple clients (such as
PCs and laptops), as shown in Figure 1-1.
LAN
DHCP Server
DHCP Client DHCP Cl
DHCP Client DH
ient
CP Client
Figure 1-1
Typical DHCP application
1.2 DHCP IP Address Assignment
1.2.1 IP Address Assignment Policy
Currently, DHCP provides the following three IP address assignment policies to meet
the requirements of different clients:
z
Manual assignment. The administrator statically binds IP addresses to few clients
with special uses (such as WWW server). Then the DHCP server assigns these
fixed IP addresses to the clients.
z
Automatic assignment. The DHCP server assigns IP addresses to DHCP clients.
The IP addresses will be occupied by the DHCP clients permanently.