Port States and Roles Flashcards
7 cards from real STP practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Port States and Roles flashcards as text
How many port states exist in the original IEEE 802.1D Spanning Tree Protocol?
Answer: 5
IEEE 802.1D STP defines five port states: Blocking, Listening, Learning, Forwarding, and Disabled.
In which STP port state does a switch port learn MAC addresses but NOT forward data frames?
Answer: Learning
In the Learning state, the port populates the MAC address table but still does not forward data frames to prevent loops.
A port in the Blocking state will do which of the following?
Answer: Receive BPDUs but not forward data frames
A Blocking port listens to BPDUs to stay informed about the STP topology but discards all data frames to prevent loops.
What is the default duration of the Listening state in IEEE 802.1D STP?
Answer: 15 seconds
The Listening state lasts for one Forward Delay period, which defaults to 15 seconds in IEEE 802.1D.
Which STP port state is functionally equivalent to the Discarding state introduced in RSTP (802.1w)?
Answer: Blocking
RSTP's Discarding state consolidates 802.1D's Blocking and Listening states, where the port neither learns MAC addresses nor forwards frames.
In which two STP port states does a port actively participate in sending and receiving BPDUs? (Choose the pair that applies)
Answer: Listening and Forwarding
Ports in the Listening and Forwarding states actively send and receive BPDUs; Blocking only receives them, and Disabled does neither.
What total time does a port transitioning from Blocking to Forwarding take by default in IEEE 802.1D?
Answer: 30 seconds
A port passes through Listening (15 s) and Learning (15 s) states, totaling 30 seconds before reaching the Forwarding state.