SMC Networks SMC7204BRA manual Configuring Bridging, Overview of Bridges

CONFIGURING BRIDGING

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.

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