Refer to the exhibit. Rapid PVST+ mode is on the same VLAN on each switch. Which switch becomes the root bridge and why?

Question

Exhibits

Options

• ASW2, because its MAC address is the highest
• BSW3, because its priority is the highest
• CSW4, because its priority is highest and its MAC address is lower
• DSW1, because its priority is the lowest and its MAC address is higher

• A
  4% (1)
• B
  8% (2)
• C
  73% (19)
• D
  15% (4)

Explanation

To determine which switch becomes the root bridge in a Rapid PVST+ network, the switch with the lowest bridge ID is selected as the root bridge. The bridge ID is a combination of the priority value and the switch MAC address. The priority value is a 4-bit value that can be set in increments of 4096, with the default value being 32768. In the exhibit, the switch priority values are not explicitly shown, so we must assume that the default value of 32768 is being used. The bridge ID of each switch is: SW1: Priority 32768, MAC address 001c.c4b6.4f80, Bridge ID 32768.001c.c4b6.4f80 SW2: Priority 32768, MAC address 001c.c4d6.b680, Bridge ID 32768.001c.c4d6.b680 SW3: Priority 32768, MAC address 001c.c4b6.e300, Bridge ID 32768.001c.c4b6.e300 SW4: Priority 4096, MAC address 000e.0c6f.9c00, Bridge ID 4096.000e.0c6f.9c00 Since SW4 has the lowest bridge ID, it becomes the root bridge.

No community discussion yet for this question.