TELINDUS 1132/1133
Web
Interface User’s Guide
Version 2.0
Page 22/57 December
2004
4.5.1.3
LAN IP address assignment with DHCP
The DHCP server can be enabled or disabled. Start IP is the number from which the DHCP
server starts issuing IP addresses. This value must be greater than the ADSL Router IP address
value. For example if the ADSL Router IP address is 192.168.1.1 (default) than the starting IP
address must be 192.168.1. 2 (or higher).
End IP is the number from which the DHCP server stops issuing IP addresses. The ending
address cannot exceed a subnet limit of 254. Hence the max value for our default gateway is
192.168.1.254. If the DHCP server runs out of DHCP addresses, users will not get access to
network resources. If this happens you can increase the Ending IP address (to the limit of 255) or
reduce the lease time.
The Lease Time is the amount of time a network user will be allowed connection to the ADSL
Router with their current dynamic IP address. The amount of time is in units of minutes; the
default value is 3600 minutes (60 hours).
Note: If you change the start or end values, make sure the values are still within the same subnet
as the router IP address. In other words, if the router IP address is 192.168.1.1 (default) and you
change the DHCP start/end IP addresses to be 192.128.1.2/192.128.1.100, you will not be able
to communicate to the ADSL Router if your PC has DHCP enabled.
In addition to the DHCP server feature, the ADSL Router supports the DHCP relay function.
When the ADSL Router is configured as DHCP server, it assigns the IP addresses to the LAN
clients. When the ADSL Router is configured as DHCP relay, it is responsible for forwarding the
requests and responses negotiating between the DHCP clients and the server. See figure 13.
Figure 13 (Example of a DHCP Relay configuration)
By turning off the DHCP server and relay the network administrator must carefully configure the
IP address, Subnet Mask and DNS settings of every computer on your network. Do not assign
the same IP address to more than one computer and your ADSL Router must be on the same
subnet as all the other computers.