When a switch has multiple links connected to a downstream switch, what is the first step that STP takes to
prevent loops?
A.
STP elects the root bridge
B.
STP selects the root port
C.
STP selects the designated port
D.
STP blocks one of the ports
Explanation:
BD
First when the switches are powered on all the ports are in Blocking state (20 sec), during this time the
+ Root Bridge is elected by exchanging BPDUs
+ The other switches will elect their Root ports
+ Every network segment will choosee their Designated port
Source: https://learningnetwork.cisco.com/thread/7677