Publication date: Sep, 2009Revision A81053-14-3. STP Port ConfigurationFunction name:STP Port SettingFunction description:In the STP Port Setting, one item selection and five parameters settings areoffered for user’s setup. User can disable and enable each port by selectingeach Port Status item. User also can set “Path Cost” and “Priority” of each portby filling in the desired value and set “Admin Edge Port” and “Admin Point ToPoint” by selecting the desired item.Fig. 3-43Parameter description:Port Status:It displays the current state of a port. We cannot manually set it becauseit displays the status only. There are three possible states. ( according to802.1w specification) DISCARDING state indicates that this port can neither forward packetsnor contribute learning knowledge.Notice: Three other states (Disable state, BLOCKING state and LISTENINGstate) defined in the 802.1d specification are now all represented asDISCARDING state. LEARNING state indicates this port can now contribute its learningknowledge but cannot forward packets still. FORWARDING state indicates this port can both contribute its learningknowledge and forward packets normally.Path Cost Status:It is the contribution value of the path through this port to Root Bridge.STP algorithm determines a best path to Root Bridge by calculating thesum of path cost contributed by all ports on this path. A port with asmaller path cost value would become the Root Port more possibly.
