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STP 802.1d Queries

I have listed few of of my understandings below in Question/Answers format.

Could someone please Verify the following and answers Q1b.

Thanks

Q1a. What happens If superior BPDU is recieved on a Blocked Port  (Port Status Blocking)

Q1b. What happens If superior BPDU is recieved on a Designated port (Port Status  Forwarding)

Q1c. What happens If Superior BPDU is recived on Root POrt (Port Status  Forwarding)

Answer#1a:

Switch stores this BPDU information for this port

and transitions the blocked port to Forwarding (via Listening & Learning)

Answer#1b:

Answer#1c

Switch stores this BPDU information for this port. The switch also forwards it with

an updated message to all attached LANs for which it is the designated switch.

--------------------------------------------------------

Q2a. What happens If inferior BPDU is recieved on a Blocked POrt  (Port Status  Blocking)

Q2b. What happens If inferior BPDU is recieved on a Desiganted port (Port Status Forwarding)

Q2c. What happens If inferior BPDU is recived on Root POrt (Port Status  Forwarding)

Answer#2a

it discards the BPDU.

IF MAX_Age time expires and the blocked port  doesn’t receive the previously stored BPDU the

port  goes immediately to listening and Switch starts sending its own better BPDU.

Answer#2b

When a Designated Port hears an inferior BPDU it sends its better Configuration BPDU in response.

Answer#2c

It discards the BPDU

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