User's Manual

UTT Technologies Chapter 7 Advanced Setup
http://www.uttglobal.com Page 152
7.8 Advanced DHCP
This section describes the Advanced > DHCP pages.
7.8.1 Introduction to DHCP
7.8.1.1 Overview
The Dynamic Host Configuration Protocol (DHCP) provides a framework for passing
configuration information to hosts on a TCP/IP network.
DHCP allows a host to be configured
automatically, eliminating the need for intervention by a network administrator. DHCP is
built on a client/server model, where one or more DHCP servers assign network
addresses and deliver other TCP/IP configuration parameters to DHCP clients (hosts). In
addition, DHCP can guarantee to avoid allocation of duplicate IP addresses, and to
reassign the IP addresses that are no longer used.
DHCP supports three mechanisms for IP address allocation:
Ɣ Automatic allocation: DHCP server assigns a permanent IP address to a client.
Ɣ Dynamic allocation: DHCP server assigns an IP address to a client for a limited
period of time, which is called a lease. The client may extend its lease with
subsequent request, and it may release the address back to the server.
Ɣ Manual allocation: A network administrator assigns an IP address to a client, and
DHCP server is used simply to convey the assigned address to the client.
A particular network will use one or more of these mechanisms, according to the actual
requirements. The dynamic allocation is the only mechanism that allows automatic reuse
of addresses that are no longer needed by the client.
7.8.1.2 DHCP Operation Process
The following describes the basic operation principle of DHCP, including the process of
requesting for a new IP address, the process of renewing an IP address, and the process
of releasing an IP address.
1. Requesting for an IP Address