D-Link DES-3250TG User Manual page 106

DES-3250TG Layer 2 Fast Ethernet Switch User's Guide
STP Port Settings
The Spanning Tree Protocol (STP) operates on two levels: on the
switch level, the settings are globally implemented. On the port
level, the settings are implemented on a user-defined Group of
ports basis.
To configure STP, click the Spanning Tree folder on the
Configuration menu and then click on the STP Port
Settings link:
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