Chapter 9: Technical Reference

BRIDGING AND ROUTING

Bridging

You can configure the Megabit Modem 410F and 420F as a bridge to forward Ethernet data based on MAC addresses.

MAC Layer Bridging

A bridge moves information across an internetwork from a source to a destination at the link layer (of an OSI reference model). The information is sent to a physical address known as a Media Access Control (MAC) address. The Megabit Modem 410F and 420F provide transparent Ethernet MAC-layer bridging. The bridge learns up to 1024 addresses.

Spanning Tree Protocol

The Megabit Modem 410F and 420F support the 802.1d Spanning Tree protocol, which eliminates loops in a LAN topology by partitioning out redundant links between LAN segments. This ensures that there is only one path, or link, between any two nodes on the network. If this link goes down, Spanning Tree re-enables partitioned links to create a new loop-free topology if possible.

An example of the active topology is shown on page 70. In this example, the spanning tree algorithm partitions out the bridge from LAN A to LAN B and the link from ENET2 to Bridge 5.

Megabit Modem 410F and 420F User Manual

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