Black Box LR5200A-R2, LR5100A-T manual Bridging, 1 Networks Bridged across a WAN link, Applications

Applications

Bridging

An Ethernet bridge intelligently forwards Ethernet data packet traffic between connected networks. The traffic may be across the Wide Area Network (illustrated below) or, in the case of the router, may be between two LANs connected to the same unit.

WAN connection

Network #1	Network #2
Windows for Workgroups Computers	Windows for Workgroups Computers

Figure 2 -1 Networks Bridged across a WAN link

Ethernet bridges simply forward information based on Ethernet MAC addresses. If a packet is destined for a device located on a different network than the device that sent the packet, the bridge will forward that packet to the connected network. If a packet is destined for a device located on the same local network as the originating device, the bridge will ignore the packet.

Ethernet bridges also communicate to each other using what is called the Spanning Tree Protocol (STP). STP is used to prevent loops in a network which cause traffic to be re- broadcast again and again causing network congestion.

The router are pre-configured to operate as an Ethernet bridge compatible with the IEEE 802.1d Spanning Tree Protocol definitions. This means that without configuration modifications, the router will bridge Ethernet traffic to its partner bridges when the Wide Area Network (WAN) connection has been established.

This product is also pre-configured as an IPX router. This means that if you wish to bridge IPX traffic instead of routing it, you must disable the IPX routing function of the router. Once IPX routing has been disabled, all IPX traffic will be bridged between networks.

To set-up a bridge between two LANs using a dual LAN router, all that is required is that the LANs be connected to the router.

To set-up a bridge between two networks connected by a WAN link:

−Connect each router to the LAN(s) it will be serving

−Connect the WAN interface of each router to the equipment supplied by the service provider

−Configure the remote site profile of the partner router if necessary

−Establish the WAN connection

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