Overview of IP Routes
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Using IP routes to define default gateways
IP routes are defined on computers, routers, and other IP-enabled
devices to instruct them which hop to take, or which gateway to
use, to help forward data along to its specified destination.
If no IP route is defined for a destination, then IP data is passed
to a predetermined default gateway. The default gateway serves
like a higher-level telephone switchboard; it may not be able to
connect directly to the destination, but it will know a set of other
devices that can help pass the data intelligently. If it cannot
determine which of these devices provides a good next hop
(because no such route has been defined), then that device will
forward the data to its default gateway. Eventually, a high-level
device, using a predefined IP route, will be able to forward the
data along a path to its destination.
Do I need to define IP routes?
Most users do not need to define IP routes. On a typical small
home or office LAN, the existing routes that set up the default
gateways for your LAN computers and for the ADSL Barricade
provide the most appropriate path for all your Internet traffic.
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On your LAN computers, a default gateway directs all Internet
traffic to the LAN port on the ADSL Barricade. Your LAN
computers know their default gateway either because you
assigned it to them when you modified their TCP/IP properties,
or because you configured them to receive the information
dynamically from a server whenever they access the Internet.
(Each of these processes is described in Quick Start,
Configuring Your Computers.)
