Inalp Networks SmartWare Release 2.10, Software Configuration Manual

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196 DHCP Configuration
22 DHCP CONFIGURATION
This chapter provides an overview of the Dynamic Host Configuration Control Protocol (DHCP) and
describes the tasks involved in configuring them. For detailed information on command syntax and
usage guidelines for the commands listed in the configuration tasks refer to Chapter 14 ???, "Context
IP Mode", Chapter 15 ???, "Interface Mode", or Chapter XX, "Profile DHCP-Server Mode" in the
SmartWare
Command Reference Guide.
This chapter includes the following sections:
• Introduction to DHCP
• DHCP-Client Configuration Tasks
•
DHCP-Server Configuration Tasks
22.1 Introduction to DHCP
The Dynamic Host Configuration Protocol (DHCP) automates the process of configuring new and
existing devices on TCP/IP networks. DHCP performs many of the same functions a network
administrator carries out when connecting a computer to a network. Replacing manual configuration
by a program adds flexibility, mobility, and control to networked computer configurations.
The tedious and time-consuming method of assigning IP addresses was replaced by automatic
distributing IP addresses. The days when a network administrator had to manually configure each
new network device before it could be used on the network are past.
In addition to distributing IP addresses, DHCP enables configuration information to be distributed in
the form of DHCP options. This options include for example, the default router address, domain
name server addresses, the name of a boot file to load etc.
A new expression in DHCP is
lease . Rather than simply assigning each DHCP-Client an IP address to
keep until the client is done with it, the DHCP-Server assigns the client an IP address with a lease;
the client is allowed to use the IP address only for the duration of that lease. When the lease expires,
the client is forced to stop using that IP address. To prevent a lease from expiring, which essentially
shuts down all network access for the client, the client must renew its lease on its IP address from
time to time.
In SmartWare a DHCP-Client and a DHCP-Server are implemented. The DHCP-Client gets IP
address and configuration information from a DHCP-Server on the WAN side of the SmartNode.
The DHCP-Server provides other clients on the LAN side with IP addresses and other configuration
information. DHCP-Server and DHCP-Client are illustrated in Figure 22-1.
Software Configuration Guide Release 2.10, Revision 1.00