What STP Does?

Previously we understood STP's main job is to Block a port on the loop to break the Loop. Let us understand What STP does to break that Loop.

To break the Loop STP put interfaces of each Switch either in a Forwarding State or in a Blocking State.
Forwarding State:
- In Forwarding State ports are Forwarding & receiving the Frames.
Blocking State:
- In Blocking State ports are not Forwarding Frame. Ports however receiving the Frames but keep on discarding them (except STP/RSTP & and some other overhead messages).
If however something changes in the LAN (e.g. a running link goes down) then the STP convergence process can also bring the blocked ports up form the Blocking to the Forwarding State.
Lets take a look at How STP works

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Last updated 3 years ago