Cisco 200-101 Exam Questions

Question 14

 Refer to the exhibit

Which switch provides the spanning-tree designated port role for the network segment that services the printers?

A. Switch1
B. Switch2
C. Switch3
D. Switch4

Answer: C
Explanation:  First, the question asks what switch services the printers, so it can be Switch 3 or Switch 4 which is connected directly to the Printers.
Designated port is a port that is in the forwarding state. All ports of the root bridge are designated ports.
Switch 3 and Switch 4 has same priority so it will see on lowest MAC address and here switch 3 has lowest MAC address. So switch 3 segment will play a Designated port role. By comparing the MAC address of Switch 3 and Switch 4 we found that the MAC of Switch 3 is smaller. Therefore the interface connected to the Printers of Switch 3 will become designated interface and the interface of Switch 4 will be blocked.