Chapter 11 Switching and Virtual LANs

What is used at layer 2 to prevent switching loops?

Spanning Tree Protocol (STP)

What does trunking provide?

Trunking allows you to send information about many or all VLANs through the same link. Access ports allow information bout only one VLAN transmitted.

When is STP said to be converged on the root bridge? (Choose two.) A. When all ports are in the forwarding state B. When all ports are in the blocking state C. When all ports are in the listening state D. When all ports are in the learning state

A, B. The sequence of steps for STP convergence is, by default, blocking, listening, learning, forwarding, disabled. When all ports are in either the blocking or forwarding state, STP is converged.

What are the distinct functions of layer 2 switching that increase available bandwidth on the network? (Choose three.) A. Address learning B. Routing C. Forwarding and filtering D. Creating network loops E. Loop avoidance F. IP addressing

A, C, E. Layer 2 features include address learning, forwarding, and filtering of the network, and loop avoidance.

What is the result of segmenting a network with a bridge (switch)? (Choose two.) A. It increases the number of collision domains B. It decreases the number of collision domains C. It increases the number of broadcast domains D. It decreases the number of broadcast domains E. It makes smaller collision domains F. It makes larger collision domains

A, E. Bridges break up collision domains, which would increase the number of collision domains in a network and also make smaller collision domains.

What are the three switch functions are layer 2?

Address learning, filtering, and loop avoidance

Switches, by default, only break up ____ domains.

Collision

Which of the following are benefits of VLAN? (Choose three.) A. They increase the size of collision domains B. They allow logical grouping of users by function C. They can enhance network security D. They increase the size of broadcast domains while decreasing the number of collision domains E. They simplify switch administration F. They increase the number of broadcast domains while decreasing the size of the broadcast domains

B, C, F. VLANs break up broadcast domains in a switched layer 2 network, which means smaller broadcast domains. They allow configuration by logical function instead of physical location and can create some security if configured correctly.

The types of ports that can be found on a switch are ___ and ___. (Choose two.) A. VLAN trunk protocol B. Access C. 802.1Q D. Trunk

B, D. Hosts are connected to a switch and are members of one VLAN. This is called an access port. Trunk links connect between switches and pass information about all VLANs.

What is a disadvantage of using port spanning? A. It breaks up broadcast domains on all ports. B. It can create overhead on the switch. C. It makes the switch one large collision domain. D. It makes the switch fast between only two ports instead of all ports

B. Be careful when using port mirroring/spanning on a switch because it can cause a lot of overhead on the switch and possibly crash your network. It's therefore a good idea to use this feature at strategic times and only for short periods, if possible.

You have multiple departments all connected to switches, with crossover cables connecting the switches together. However, response time on the network is still very slow even though you have upgraded from hubs to switches. What technology should you implement to improve response time on the networks? A. STP B. VLANs C. Convergence D. OSPF

B. Switches break up collision domains by default, but the network is still one large broadcast domain. In order to break up broadcast domains in a Layer 2 switched network, you need to create virtual LANs.

Which of the following statements is true? A. A switch creates a single collision domain and a single broadcast domain. A router creates a single collision domain B. A switch creates separate collision domains but one broadcast domain. A router provides a separate broadcast domain C. A switch creates a single collision domain and separate broadcast domains. A router provides a separate broadcast domain as well D. A switch creates separate collision domains and separate broadcast domains. A router provides separate collision domains

B. Switches break up collision domains, and routers break up broadcast domains.

Which of the following is a layer 2 protocol used to maintain a loop-free network? A. VTP B. STP C. RIP D. CDP

B. The Spanning Tree Protocol is used to stop switching loops in a switched network with redundant paths.

VLANs break up ___ domains in a layer 2 switched network.

Broadcast

In which two states is the MAC address table populated with addresses? (Choose two.) A. Blocking B. Listening C. Learning D. Forwarding

C, D. In the blocking and listening states, the MAC address table is not learning. Only in the learning and forwarding states is the MAC address table learning MAC addresses and populating the MAC address table.

Which of the following are IEEE versions of STP? (Choose two.) A. 802.1X B. VLANs C. 802.1D D. 802.11 E. 802.1W

C, E. Both 802.1D and 802.1w are IEEE STP versions, with 802.1w being the latest and greatest version.

If a switch receives a frame and the source MAC address is not in the MAC address table but the destination address is, what will the switch do with the frame? A. Discard it and send an error message back to the originating host B. Flood the network with the frame C. Add the source address and port to the MAC address table and forward the frame out the destination port D. Add the destination to the MAC address table and then forward the frame

C. Because the source MAC address is not in the MAC address table, the switch will add the source address and the port it is connected to into the MAC address table and then forward the frame to the outgoing port.

If you are configuring voice VLANs, which of the following should you configure on the switch ports to provide a higher precedence to voice traffic over data traffic to improve sound quality? A. Access VLANs B. VTP C. QoS D. STP

C. If you are configuring voice VLANs, you'll want to configure Quality of Service (QoS) on the switch ports to provide a higher precedence to voice traffic over data traffic to improve quality of the line.

You connect your host to a switch that is running network analysis software. However, you are not seeing any packets from the server. What do you need to implement on the switch to see all the packet information? A. VLANs B. STP C. Port mirroring D. Authentication

C. In order to see all frames that pass through the switch and read the packets with a network analyzer, you need to enable port mirroring on the port your diagnostic host is plugged into.

Which of the following features of a switch will allow two switches to pass VLAN network information? A. PoE B. VLANs C. Trunking D. STP

C. Trunking allows switches to pass information about many or all VLANs configured on the switches.

Which switching technology reduces the size of a broadcast domain? A. ISL B. 802.1Q C. VLANs D. STP

C. Virtual LANs break up broadcast domains in layer 2 switched internetworks.

What does a switch do when a frame is received on an interface and the destination hardware address is unknown or not in the filter table? A. Forwards the switch to the first available link B. Drops the frame C. With the exception of the source port, floods the network with the frame looking for the device D. Sends back a message to the originating station asking for a name resolution

C. With the exception of the source port, switches flood all frames that have an unknown destination address. If a device answers the frame, the switch will update the MAC address table to reflect the location of the device.

You need to implement a separate network for contractors and guests working at your office. Which technology should you implement?

Create a VLAN for contractors and another VLAN for guests.

You connect a host to a switch port, but the new host cannot log into the server that is plugged into the same switch .What could the problem be? (Choose two.) A. The router is not configured for the new host B. The STP configuration on the switch is not updated for the new host C. The host has an invalid MAC address D. The switch port the host is connected to is not configured to the correct VLAN membership E. STP shut down the port

D, E. The best answers are that the VLAN membership for the port is configured incorrectly and that STP shut down the port.

You want to improve network performance by increasing the bandwidth available to hosts and limiting the size of the broadcast domains. Which of the following options will achieve this goal? A. Managed hubs B. Bridges C. Switches D. Switches configured with VLANs

D. By creating and implementing VLANs in your switched network, you can break up broadcast domain at layer 2. For hosts on different VLANs to communicate, you must have a router or layer 3 switch.

When would you configure VTP on a switch? A. When you have hubs connected in your network B. When you have redundant links between switches C. When you have multiple hosts in multiple VLANs and you want to share all the data between hosts without a router D. When you have multiple switches with multiple VLANs and you want to share the VLAN database from one switch to all the others

D. Virtual Trunk Protocol (VTP) is a Cisco proprietary method of having a single VLAN database advertised to all other switches in your network. This allows for ease of VLAN management in a larger network.

If a destination MAC address is not in the forward/filter table, what will the switch do with the frame?

Flood the frame out all ports except the port on which it was received.

If a frame is received on a switch port and the source MAC address is not in the forward/filter table, what will the switch do?

It will add the source MAC address to the forward/filter table.

You need to power a device such as an access point or IP phone. What protocol can provide power to these devices over an ethernet cable?

Power over Ethernet (PoE)

You plug a host into a switch port and the host receives an IP address but the user can't get to the services it needs. What is probably the problem?

The VLAN port membership is set wrong.