Practice Test Geeks(ICND1) Interconnecting Cisco Networking Devices Part 1 Practice Test
← All ICND1 Flashcard Decks

Spanning Tree Protocol (STP) Flashcards

7 cards from real ICND1 practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Spanning Tree Protocol (STP) flashcards as text

  1. Which IEEE standard defines Rapid Spanning Tree Protocol (RSTP)?

    Answer: IEEE 802.1W

    IEEE 802.1W defines RSTP, which was later incorporated into the revised 802.1D-2004 standard for faster convergence.

  2. What is the primary improvement that RSTP provides over traditional STP?

    Answer: Significantly faster convergence time

    RSTP converges in seconds rather than up to 50 seconds for traditional STP by using a peer negotiation mechanism instead of fixed timers.

  3. In RSTP, which port role provides a redundant path to the Root Bridge and can quickly replace the Root Port if it fails?

    Answer: Alternate Port

    The Alternate Port in RSTP offers an alternate path to the Root Bridge and transitions rapidly to Root Port if the current Root Port goes down.

  4. What does Cisco's Per-VLAN Spanning Tree Plus (PVST+) do differently from standard 802.1D STP?

    Answer: It runs a separate STP instance for each VLAN, allowing per-VLAN Root Bridge placement

    PVST+ runs an independent STP instance per VLAN, enabling per-VLAN Root Bridge elections and traffic load balancing across redundant links.

  5. What does the Cisco STP PortFast feature do when configured on a switch access port?

    Answer: It allows the port to bypass Listening and Learning and go directly to Forwarding

    PortFast causes a port to immediately enter the Forwarding state upon link-up, skipping the Listening and Learning transitional states.

  6. What action does BPDU Guard take when a BPDU is received on a PortFast-enabled port?

    Answer: It places the port into an err-disabled state

    BPDU Guard immediately shuts down the port into err-disabled state when a BPDU is detected, protecting the STP topology from unauthorized switches.

  7. In RSTP, which port role is functionally equivalent to the Root Port in traditional 802.1D STP?

    Answer: Root Port

    RSTP retains the Root Port role with the same definition as 802.1D: the port on each non-root switch with the lowest-cost path to the Root Bridge.