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kelvinwgr

Hi can someone explain to me in lag man term what is the difference between a root port, root switch, designated port and designated switch.

Sometimes I also come across root bridge. I am confused over all these. Can somebody enlighten me? Thanks
It takes time to get used to the terminology, it can be confusing.

This video explains most if not all the STP terms you mentioned and gives a good overview of the STP protocol.

http://www.youtube.com/watch?v=ihF_78oIaDI

Also Root Switch = Root Bridge = Designated Switch. They are different names for the same thing.


The Root Bridge/Switch is the Main Switch in the STP Topology, chosen by election.
A designated port is one that is active and forwarding traffic.
A Blocked port is one that is not active or forwarding traffic.
A Root Port is an active port that leads to the Root Bridge.

A designated port is either connected to a Root Port or a Blocked Port.
A Root Port is either connected to the Root Bridge or to another designated port but never a blocked port.
All ports on the Root Bridge/Switch are Designated ports by default as there are no blocking ports on a Root Bridge

HTH

kelvinwgr

Hi ciscok1d,

Thanks for the precise and straight forward explanation. I had a hard time reading the chunks of paragraphs explained on other websites.

I am taking my ccna exam 640-802 next week, so it's better if I can clarify these confusion.  =)