Spanning Tree Protocol Questions and Answers

Answer: A

Correct answer: 1 and 5

Each port becomes its own collision domain, so segmenting with a switch both increases the number of collision domains and makes each of them smaller - two ways of stating the same result, which is why both statements are correct. Broadcast domains are unaffected, since a switch floods broadcasts throughout; dividing those requires a router or VLANs.

Answer: A

Correct answer: Switch(config)# spanning-tree mode rapid-pvst

Two things must be right. The command is entered in global configuration mode, not privileged exec, and the keyword is rapid-pvst rather than the standard’s number - IOS names the mode after the implementation, Rapid Per-VLAN Spanning Tree, not after 802.1w.

Answer: C

Correct answer: To prevent switching loops in networks with redundant switched paths

STP operates at layer 2 and prevents *switching* loops, which is the distinction the option beside it trades on - routing loops are a layer 3 problem handled by the routing protocols. It works by blocking ports until only one active path remains between any two points, keeping the redundant links in reserve.

Answer: B

The switchport port-security is an important command, and it's super easy with the CNA; however, from the CLI, you can set the maximum number of MAC addresses allowed into the port, and then set the penalty if this maximum has been passed.

Answer: C

Correct answer: show mac address-table

show mac address-table displays the forward/filter table - each learned MAC address, the VLAN it was seen in, the port it was learned on and whether the entry is dynamic or static. It is the first place to look when traffic is going to the wrong port or being flooded when it should not be.

Answer: B

Correct answer: A switch creates separate collision domains but one broadcast domain. A router provides a separate broadcast domain.

Each switch port is its own collision domain, which is what removes contention, but a broadcast is flooded to every port, so the whole switch remains one broadcast domain. A router does not forward broadcasts, so each of its interfaces is a separate broadcast domain - which is why routing, or VLANs with routing between them, is what actually divides a large flat network.