Bridging Configuration; Bridging Overview; Introduction To Bridging; Major Functionalities Of Bridges - 3Com MSR 50 Series Configuration Manual

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Bridging Overview

Introduction to Bridging

Major Functionalities of
Bridges
B
RIDGING
When configuring bridging functionalities, go to the following sections for the
information you are interested in:
"Bridging Overview" on page 405
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"Bridging Configuration Task List" on page 409
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"Displaying and Maintaining Bridging Configurations" on page 412
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"Transparent Bridging Configuration Examples" on page 412
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Presently the devices support only transparent bridging, so this document provides
information about transparent bridging only.
A bridge is a store-and-forward device that connects and transfers traffic between
local area network (LAN) segments at the data-link layer. In some small-sized
networks, especially those with dispersed distribution of users, the use of bridges
can reduce the network maintenance costs, without requiring the end users to
perform special configurations on the devices.
In applications, there are four major kinds of bridging technologies: transparent
bridging, source-route bridging (SRB), translational bridging, and source-route
translational bridging (SR/TLB).
Transparent bridging is used to bridge LAN segments of the same physical media
type, primarily in Ethernet environments. Typically, a transparent bridging device
keeps a bridge table, which contains mappings between destination MAC
addresses and outbound interfaces.
Presently the devices support the following transparent bridging features:
Bridging over Ethernet
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Bridging over point-to-point (PPP) and high-level data link control (HDLC) links
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Bridging over X.25 links
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Bridging over frame relay (FR) links
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Inter-VLAN transparent bridging
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Routing and bridging are simultaneously supported
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Maintaining the bridge table
A bridge relies on its bridge table to forward data. A bridge table consists two
parts: MAC address list and interface list. Once connected to a physical LAN
C
ONFIGURATION