STP Advanced Features and Variants 3

Question 1

Which STP protection feature should be enabled on all access ports connected to end devices to prevent them from participating in STP topology changes?

Accepted Answer

BPDU Guard

Answer

Root Guard

Answer

Loop Guard

Answer

UDLD

Question 2

What does the STP Backbone Fast feature do when an indirect link failure is detected?

Accepted Answer

Allows a switch to use an alternate port without waiting for MaxAge by sending RLQ messages

Answer

Immediately flushes the MAC table and starts a new election

Answer

Enables the port to skip the Listening state

Answer

Sends a TCN BPDU to all ports simultaneously

Question 3

STP UplinkFast is most beneficial in which network scenario?

Accepted Answer

Access layer switches with one uplink active and one in blocking state

Answer

Core switches with many redundant equal-cost links

Answer

Distribution switches running MSTP with multiple instances

Answer

Routed access layer deployments with no STP needed

Question 4

In MSTP, what is IST (Internal Spanning Tree)?

Accepted Answer

Instance 0 inside an MST region that carries unassigned VLANs and connects to the CIST

Answer

A separate spanning tree that runs between MST regions only

Answer

The instance dedicated to management VLAN traffic

Answer

A term for RSTP running inside a single VLAN

Question 5

Which RSTP port role forwards traffic and is elected based on lowest path cost to the root bridge?

Accepted Answer

Root Port

Answer

Alternate Port

Answer

Backup Port

Answer

Designated Port

Question 6

What distinguishes an RSTP Alternate Port from a Backup Port?

Accepted Answer

Alternate provides a redundant path to the root via a different switch; Backup provides redundancy on the same switch/segment

Answer

Alternate is used only in MSTP; Backup is used only in PVST+

Answer

Alternate connects to the root bridge; Backup connects to downstream switches

Answer

There is no difference; they are synonyms in 802.1w

Question 7

When configuring MSTP on Cisco switches, which command sets the MST region name?

Accepted Answer

spanning-tree mst configuration name <name>

Answer

spanning-tree mst name <name>

Answer

spanning-tree region <name>

Answer

mst region-name <name>