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In this video we're going to discuss spending tree spending tree was developed to stop a layer two loops

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occurring in switched environments.

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In transparent switching or transparent bridging which is what Ethernet uses redundant links introduce

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loops and spanning trees used to stop those loops spanning tree has been around for many years and there

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have been multiple developments and enhancements.

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So this is one of the challenges that she's going to face.

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There are different implementations and versions of spanning tree and you'll need to know some of those

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differences.

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Spending trees are very important protocol in traditional networks.

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And once again its primary purpose is to stop loops in a switched environment and not necessarily to

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stop them as quickly as we would like.

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Spending was developed many years ago originally being developed for bridges rather than switches and

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thus at times is very slow to converge.

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In other words it takes a long time for traffic to be rerouted.

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If there's a change in the network topology spanning tree was once again originally developed for bridges

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and bridges did the calculations in software rather than in hardware which is what switches do today.

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So in the past slower convergence was fine but that's a major problem in todays environments where we

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run voice of IP or other protocols that require a very quick convergence.

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Thus the original standard spending three or eight or two to one d spanning tree has been superseded

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by newer versions such as rapid a spanning tree and multiple spanning tree because spending trees are

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of great importance for the CC and a certification as well as for real deployments.

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I'm going to start off with the original version of spanning tree Ada to the one d.

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And then we'll build on those concepts.

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Looking at more and more complex typologies and other versions of spanning tree.