4-Port ADSL Router User Manual

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C
ONFIGURING
B
RIDGING
The ADSL Barricade can be configured to act as a bridging
device between your LAN and your ISP. Bridges are
devices that
enable two or more networks to communicate as
if they are two
segments of the same physical LAN. This section describes how
to configure
the ADSL Barricade to operate as a bridge.
Note:
Before changing your bridge configuration, check with
your ISP to determine the type of connection they use
to exchange data with their customer's DSL modems
(such as Ethernet bridging or IP routing).
Overview of Bridges
A bridge is a device used to connect two or more networks so they
can exchange data. A bridge learns the unique manufacturer-
assigned hardware IDs of each computer or device on both (or all)
networks it is attached to. It learns that some of the IDs represent
computers attached via one of the device's interfaces and others
represent computers connected via other interfaces. For example,
the hardware IDs of your home computers are attached via the
Ethernet port, and the hardware IDs of your ISP's computers are
attached via the WAN (DSL) port. It stores the ID list and the
interface associated with each ID in its bridge forwarding table.
When the bridge receives a data packet, it compares its destination
hardware ID to the entries in the bridge forwarding table. When the
packet's ID matches one of the entries, it forwards the packet
through the interface that connects to the corresponding network.
Note:
The bridge does not send the data directly to the
receiving
computer, but broadcasts it to the receiving
network, making it available to any node on that
network.