SMC Networks EliteConnect SMC2891W-AG User Manual page 75

6
Advanced Configuration
Spanning Tree Protocol – STP uses a distributed algorithm to select a bridging
device (STP-compliant switch, bridge or router) that serves as the root of the
spanning tree network. It selects a root port on each bridging device (except for the
root device) which incurs the lowest path cost when forwarding a packet from that
device to the root device. Then it selects a designated bridging device from each
LAN which incurs the lowest path cost when forwarding a packet from that LAN to
the root device. All ports connected to designated bridging devices are assigned as
designated ports. After determining the lowest cost spanning tree, it enables all root
ports and designated ports, and disables all other ports. Network packets are
therefore only forwarded between root ports and designated ports, eliminating any
possible network loops.
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