Clinical & Scientific Knowledge 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 Clinical & Scientific Knowledge flashcards as text
What is the purpose of the PortFast feature in STP?
Answer: Allows edge ports to skip Listening and Learning states
PortFast allows access layer ports connected to end hosts to immediately transition to Forwarding, bypassing Listening and Learning.
Which field in the Bridge ID has the highest priority during root bridge election?
Answer: Bridge priority
The bridge priority (default 32768) is compared first; the MAC address is only used as a tiebreaker.
BPDUGuard is enabled on a PortFast port. What happens when a BPDU is received?
Answer: The port is placed in err-disabled state
BPDUGuard shuts down a PortFast port by placing it in err-disabled state if any BPDU is received.
In RSTP (802.1w), which port role replaces the STP Blocking state ports?
Answer: Alternate and Backup ports
RSTP introduces Alternate (replaces blocked non-designated) and Backup (provides redundancy on shared segments) port roles.
What STP path cost value is assigned to a 1 Gbps link using the original (short) path cost method?
Answer: 4
Using the original 802.1D short path cost method, a 1 Gbps link has a cost of 4.
A switch has two equal-cost paths to the root bridge through different upstream switches. How does STP break this tie?
Answer: By choosing the path through the switch with the lowest Bridge ID
When root path cost is tied, STP selects the path through the upstream switch with the lowest Bridge ID.
What does the STP MaxAge timer control?
Answer: How long a switch stores BPDU information before discarding it
MaxAge (default 20 seconds) is the maximum time a switch retains BPDU information before considering the root bridge unreachable.