Longshine LCS-SW1420S Manual Del Usuario página 43

STA
The Spanning Tree Algorithm (STA) outlined in IEEE 802.1D can avoid network
looping but coexist with linking backup. This feature permits STA-aware switches
interact with each other. This can ensure only one route exists between any two
devices on the network. If looping is detected (maybe implements on purpose for
linking backup), looping ports will be blocked to discard additional route. If one using
route fails, this Spanning Tree Algorithm automatically releases the blocking port and
establishes connection with other devices.
Since a STA network has been established, all devices listen for Hello BPDUs (Bridge
Protocol Data Units) sent from the Root Bridge. After the Max Age maximum time is
up, the device supposes that the route to the Root Bridge is down. The devices initiate
negotiations with each other to reconfigure the network for a valid topology.
Root Device
E-42