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So here's a quick comparison of the different versions of Spending Tree.

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The spending tree A to one DX protocol doesn't need a lot of resources but is slow to converge.

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You only have one spanning tree instance for your entire layer to network.

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This can lead to suboptimal traffic flows and ADA 2 to 1 DX is generally not used today in Cisco environments.

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Just be aware that when you use newer versions of spanning tree Cisco switches or backward compatible

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and can talk to older switches or non Cisco switches using edited edit2 one DX PVS DT is the Cisco enhancement

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that provides a single instance of spending tree per VLAN.

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It's just a proprietary.

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It needs more resources because one spanning tree instance is created per VLAN.

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It is still slow to converge but does allow you to split traffic flows because you have one spanning

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tree instance per VLAN.

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As an example VLAN one traffic could use one uplink, but VLAN two traffic could use a separate uplink

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or a separate port in a network.

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Cisco have also enhanced PVS.

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RT with features such as Port Fast UpLink, Fast Backbone, Fast BPU, Guard, BPD, Filter, Root,

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guard and Loop Guard.

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We'll discuss some of those terms in this course.

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Otherwise, you'll learn more about those when you attend your camp.

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Course's rapids spanning tree protocol or ADA 2 to 1 W is an industry standard protocol.

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It doesn't need as many resources as PVS plus because it supports a single instance of spanning tree

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for your layer two network.

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Its big advantage is that it provides very quick or fast convergence.

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It also doesn't address suboptimal traffic flow issues because you can't send VLAN ten traffic for example

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down one link and VLAN 20 traffic down another link.

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That's the advantage of rapid PvP plus.

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Rapid PvP plus incorporates the advantages of rapid spanning tree, but allows you to create one spanning

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tree instance per VLAN so you can do load sharing of traffic.

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It provides a very quick convergence but uses a lot of resources, especially when you've got many VLANs.

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The advantage of multiple spanning tree is that it solves the high resource issue of PVP plus multiple

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spending.

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Tree allows you to create a instance of spanning tree and then map various VLANs to that instance.

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As an example, once again, if you had 200 VLANs, PvP or rapid PvP would require 200 instances of

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spanning tree, whereas multiple spanning tree could use two instances to do load sharing and reduce

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the amount of resources required.

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So CPU and memory requirements for multiple spanning tree are lower than those for rapid PVP plus,

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but resources are higher than those for rapid spanning tree.

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Now you may find reference materials stating that PvP plus is the default spanning tree on Cisco switches.

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That really depends.

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A lot of switches today.

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Use rapid PvP as the default version of spanning tree.