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Startup and Steady State

Startup

When the bridge boots up, its address list is empty.
This state is called startup state.

Steady State

When the bridge has received at least one frame from every computer, its address list is built.
This state is called steady state.

Planning a Bridge

Since bridges are used to divide LAN into segments, the computers who communicate frequently can be placed into same segment.
This improves the performance of the network because traffic on one segment does not affects the traffic on other segment.

Bridging between Building

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Advantages

  1. The fiber optic connecting both buildings doesn't need to be disturbed while connecting or disconnecting computers to the network.
  2. Traffic at one building doesn't affects the other building.

Building across Longer Distance

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Since the bandwidth is very low, the bridge has to store data into its memory and wait till it can be send to the satellite for communication but it may run out of memory.
Therefore, the communication software waits for a response after sending few frames.

A Cycle Bridges

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Sometimes, a network can become cyclic as such:
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Problem here is that if a broadcast signal is sent, it never terminates and keeps looping around, causing infinite copies.

Distributed Spanning Tree

In this cyclic case, the bridges communicate with each other and automatically decide through DST algorithm that which bridge will not forward the broadcast frames and which one will do.