Product guide

Spanning-Tree Operation
The RSTP (802.1w) and STP (802.1D) Spanning Tree Options (5300xl, 3400/6400cl switches)
Problem:
STP enabled with 2
separate (non-trunked)
links blocks a VLAN link.
Solution:
STP enabled with
one trunked link.
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.
Figure 6-3. Example of Using a Trunked Link with STP and VLANs
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