The RSTP (802.1w) and STP (802.1D) Spanning Tree Options
dant links by using a port trunk. The following example shows how you can use a port trunk with 802.1Q (tagged) VLANs and spanning tree without unnecessarily blocking any links or losing any bandwidth.
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STP enabled with 2 |
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| STP enabled with |
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separate |
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| one trunked link. |
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links blocks a VLAN link. |
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Nodes 1 and 2 cannot communicate because STP is blocking the link.
Nodes 1 and 2 can communicate because STP sees the trunk as a single link and 802.1Q (tagged) VLANs enable the use of one (trunked) link for both VLANs.