Cisco Exam Questions

Which Cisco Catalyst feature automatically disables the port in an operational PortFast upon receipt

Which Cisco Catalyst feature automatically disables the port in an operational PortFast upon
receipt of a BPDU?

A.
BackboneFast

B.
UplinkFast

C.
Root Guard

D.
BPDU Guard

E.
BPDU Filter

Explanation:
We only enable PortFast feature on access ports (ports connected to end stations). But if
someone does not know he can accidentally plug that port to another switch and a loop may
occur when BPDUs are being transmitted and received on these ports.
With BPDU Guard, when a PortFast receives a BPDU, it will be shut down to prevent a loop.