UNDERSTANDING CONFIGURATION PARAMETERS
UNDERSTANDING CONFIGURATION PARAMETERS
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The subnet of LAN IP addresses that the router assigns are based on
a single DHCP IP Address. All traffic going to and from the subnet of
Private IP addresses goes through the DHCP IP Address. The DHCP
IP Address can be a single, fixed Public IP address, an ISP-assigned
WAN IP address, or a LAN IP address.
For situations where a LAN IP address is assigned as the DHCP IP
Address, a WAN IP address will have to be assigned to the NAT IP
Address, and NAT has to be enabled so that the DHCP IP Address
can be translated into a WAN IP address.
Unnumbered WAN IP Address
Some network devices do not use WAN IP addresses when
negotiating a connection. This is known as unnumbered IP. When
running unnumbered IP, no WAN IP addresses are used, but the LAN
IP addresses are used instead.
Terminology for Configuration Parameters
Domain Name System (DNS) IP Address
The DNS IP Address is the IP Address for your Domain Name Server.
This IP Address or Internet Protocol Address identifies the domain
name’s server to the network and the Internet.
IP Packet Filtering
Establishing IP packet filters allows you to monitor and selectively
filter packets that enter or leave the NetDSL. You can use filtering to
protect your network from unauthorized access, and restrict certain
web traffic from leaving your LAN. This is done by examining each
packet that enters the NetDSL to see if the following characteristics
match the criteria for the filter (true), or whether they do not match
(false):
IP address
: identifies each device on a TCP/IP network and
the Internet.
Subnet mask
: a series of bits designed to ‘mask’ certain portions
of an IP address.
TCP/IP port
: used to distinguish between requests for different
services, such as telnet, ftp, or the web.
Protocol type
: a set of rules governing the information flow
within a communications infrastructure.
