STP (Spanning Tree Protocol)

Hello BPDU are send every 2 seconds which contains Root cost, BID & RB ID.

RB creates & sends Hello BPDU with root cost as 0 out to all it's working interfaces (those in forwarding state)
Remaining Non-Root Bridges will receive this Hello on their Root Port.
Non-Root Bridges will then create & forward Hello BPDU including their Root cost, their BID as sender BID & RB ID to all their Designated Ports.
Step 1 & 2 repeats until something changes.
STP goes through these following States initially as well as during the convergence.
RSTP is the enhancement of STP.
If you don't want your ports to be blocked by STP/RSTP then you may use Ether Channel Protocols
You can enable PortFast manually on STP running Switch's Edge ports to skip the un-necessary Listening & Learning State.
Another method of preventing Loop / preventing hackers attack is using BPDU Guard
There are different types of STP Versions
Lets take a look at Why STP , What STP does, How STP does it & STP Messages
And finally how an Admin can change the STP Settings Statically
STP uses STP TImers after the convergence.

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Last updated 5 years ago