Deck 8: Backbone Networks

Question 1

The distribution layer of a backbone connects LANs together.

Answer 1

True

Question 2

Switches and routers are devices that can connect networks to the BN.

Answer 2

True

Question 3

A backbone network that connects many backbone networks spanning several buildings at a single location is often called an Internet backbone.

Answer 3

False

Question 4

A routed backbone tends to be used more for large networks than VLANs, although VLAN high speed switches and this new type of LAN-BN architecture are now being considered.

Question 5

Routers operate at the application layer.

Question 6

One difference between a switch and a router is that a router will only process messages addressed to the router, while a switch processes all messages.

Question 7

Layer-3 switches switch messages based on their data link layer address.

Question 8

Routers connect two or more network segments that use the same or different data link protocols, but the same network protocol.

Question 9

One advantage of a routed backbone is that is requires little management.

Question 10

The primary advantage of a routed backbone is that it clearly segments each part of the network connected to the backbone because each segment has its own subnet addresses that can be managed separately.

Question 11

A room that contains a rack of equipment for a rack-based collapsed backbone is also called the main distribution facility MDF) or central distribution facility CDF).

Question 12

One basic component of a backbone network is the hardware device that connects other networks to the backbone.

Question 13

A backbone network is a high-speed network that connects many networks

Question 14

Routers use network layer address to forward packets between network segments.

Question 15

The cable to connect BNs is usually twisted pair.

Question 16

A hardware device that operates at the application layer is a router.

Question 17

A switched backbone uses a bus topology

Question 18

Routed backbones use switches that move packets based on data link layer addresses.

Question 19

Backbone networks typically use lower speed circuits to interconnect a series of LANs and provide connections to other backbone networks.

Question 20

Routers can only connect the same type of cable.

Question 21

Switched backbone networks:

A)always use a ring topology
B)are the least common type of BN used in one building
C)use a star topology with one device, usually a switch
D)have a great deal of cable in their backbones
E)tend to have less cable, but more network devices

Question 22

A VLAN network assigns computers to LAN segments by hardware.

Question 23

Routers:

A)operate at the application layer
B)operate only at the physical layer
C)cannot connect two or more networks that use the same type of cable
D)may also be called TCP/IP gateways
E)operate only at the data link layer

Question 24

Which of the following is not true about switched backbones?

A)performance is improved over traditional bridged or routed) backbone networks
B)each connection into the switch is a separate point-to-point circuit which supports simultaneous access by the LANs connected to the switch
C)there are many more networking devices in a switched backbone network
D)if the switch fails, so does the entire backbone network
E)the backbone essentially exists in the switch; there is no backbone cable

Question 25

_________ have no backbone cable.

A)Switched backbones
B)Cloud routed backbones
C)Hubbed backbones
D)Bridged backbones
E)Multistation access unit backbones

Question 26

Which of the following is not true about Layer-3 switches?

A)They switch messages based on their IP address.
B)They can be used in place of routers.
C)They function faster than routers.
D)They have more simultaneously active ports than routers.
E)They can only switch messages based on their data link layer addresses.

Question 27

A _____________ type of BN segments each of which has a special set of subnet addresses that can be managed by different network managers) each part of the network connected to the backbone.

A)bridged backbone
B)virtual LAN
C)hubbed backbone
D)collapsed backbone
E)routed backbone

Question 28

Switches:

A)learn addresses by reading the source and destination addresses
B)operate at the physical layer only
C)connect two ore more network segments that use different data link protocols
D)connect two or more network segments that use different network protocols
E)have become more popular than layer 2 switches

Question 29

A __________ type of BN has a star topology with one device, such as a switch, at its center.

A)Bridged backbone
B)Virtual LAN
C)Hubbed backbone
D)Switched backbone
E)Routed backbone

Question 30

VLANs provide faster performance compared to switched, collapsed or routed backbone architectures.

Question 31

A subnetted or hierarchical backbone can also be called:

A)Bridged backbone
B)Virtual LAN
C)Hubbed backbone
D)Collapsed backbone
E)Routed backbone

Question 32

Routers:

A)require more management than switches
B)are not susceptible to time delays
C)use data link layer addresses to move packets that leave the subnet
D)require only a few set of TCP/IP addresses
E)don't need much time to establish separate subnet addresses for each LAN

Question 33

A VLAN requires the computer manager to reconfigure the physical cables to the switch if a computer is moved from one port to another port on a switch.

Question 34

A key advantage of a chassis switch is its flexibility.

Question 35

Which of the following is a fundamental backbone network architecture?

A)Bridged backbone
B)Virtual LAN
C)Hubbed backbone
D)Gatewayed backbone
E)Virtual backbone

Question 36

Which of the following is not true about backbone networks?

A)They may also be called enterprise networks if they connect all networks within an organization.
B)They typically connect many networks, including LANs.
C)They typically provide connections to other BNs, WANs, MANs, and the Internet.
D)They may also be called campus networks if they connect many BNs spanning several buildings as a single location.
E)They tend to use lower speed circuits than LANs.

Question 37

Which of the following is not a technology layer that is considered when designing backbone networks?

A)access layer
B)distribution layer
C)decentralized layer
D)core layer
E)none of the options

Question 38

_________ move packets along the backbone based on their network layer address.

A)Bridged backbones
B)Hubbed backbones
C)Multistation access unit backbones
D)Routed backbones
E)NIC backbones

Question 39

Which of the following is not a type of hardware device that can be used to interconnect networks?

A)layer 3 switches
B)routers
C)dumb terminals
D)layer 2 switches
E)all of the above can be used

Question 40

Which of the following is not a way that a router differs from a switch?

A)routers can connect two or more networks that use the same data link protocol
B)routers only process messages that are specifically addressed to it
C)routers operate at the network layer
D)routers perform more processing on each message than switch
E)routers can choose the "best" route between networks for forwarding a packet

Question 41

The biggest drawbacks to VLANs are their_________________.

A)cost and management complexity
B)size and contention
C)contention and cost
D)learning curve and contention
E)speed and size

Question 42

Which of the following would not be part of an "ideal" backbone design for the future?

A)access layer composed of 10/100 layer 2 Ethernet switches
B)distribution layer composed of layer 3 Ethernet switches of 100 or 1000) Base-T
C)redundant switches
D)core layer composed of layer 3 Ethernet switches running 10 or 40) GbE over fiber
E)coax cabling throughout LANs and BN

Question 43

What is a backbone network? What is typical of this kind of network?

Question 44

Which of the following would be least effective in improving backbone performance?

A)improving the computers in the network
B)changing the demand placed on the network
C)adding new keyboards to the client computers
D)upgrading the circuits between computers
E)improving devices in the network

Question 45

The _________ is the part of the backbone that connects the different backbones together.

A)Access layer
B)Distribution layer
C)Core layer
D)Privacy layer
E)Switched layer

Question 46

Using ______ capabilities, network managers can connect VOIP phones directly into a VLAN switch and configure the switch to reserve sufficient network capacity so that they will always be able to send and receive voice messages.

A) backbone
B) switched
C) routed
D)QoS
E)access

Question 47

Network demand will not be reduced by:

A)restricting or moving) applications such as desktop videoconferencing
B)using network devices to ensure that broadcast messages do not go to other networks
C)encouraging the use of applications such as medical imaging
D)sending status information to all computers on all LANs in the backbone network
E)restricting or moving) applications such as multimedia

Question 48

The backbone architecture layer that is closest to the users is the

A)Access layer
B)Distribution layer
C)Core layer
D)Privacy layer
E)Switched layer

Question 49

A _____________ type of BN is a new type of LAN/BN architecture made possible by intelligent, high speed switches that assign computers to LAN segments via software, rather than by hardware.

A)Bridged backbone
B)Virtual LAN
C)Hubbed backbone
D)Collapsed backbone
E)Routed backbone

Question 50

Which of the following is true regarding switched backbones?

A)They place all network devices for one part of the building physically in the same room, often in a rack of equipment
B)They have an advantage of requiring less cable
C)They make it more difficult to move computers from one LAN to another
D)Network capacity is always tied to the physical location of the computers
E)They are harder to maintain and upgrade than a BN that is not rack-based

Question 51

Devices in a rack are connected together using ___________.

A)patch cables
B)string
C)servers
D)modules
E)chassis switches

Question 52

Device performance on a backbone network will not be improved by:

A)using the same protocols in the backbone and the LANs
B)using static routing in low to moderate traffic conditions
C)ensuring that backbone devices have sufficient memory so that packets do not have to be retransmitted by the sender
D)translating packets from one protocol to another as they enter the BN
E)none of the options

Question 53

Associated with a switched backbone, MDF is an acronym for:

A)multi-station device foundation
B)main distribution facility
C)manual data frequency
D)multiplexer downstream flow
E)maximum data facility

Question 54

With a switched backbone network, the equipment is usually placed in a ______.

A)server
B)NIC
C)cabinet
D)basement
E)rack

Question 55

Circuit capacity on a backbone network will not be improved by:

A)going from 100Base-T Ethernet to 10Base-T Ethernet
B)going from 100Base-T Ethernet to gigabit Ethernet
C)adding additional circuits alongside heavily used ones
D)replacing a shared circuit backbone with a switched circuit backbone
E)providing a faster circuit to the server

Question 56

Which of the following is not true about multiswitch VLANs?

A)Several switches are used to build a VLAN
B)The switches in the VLAN can send packets among themselves in a way that identifies the VLAN to which the packet belongs.
C)In some multi-switch VLANs, the Ethernet packet is modified based on the emerging IEEE 802.1q standard.
D)In some multi-switch VLANs, a new VLAN packet encapsulates the Ethernet packet.
E)All of the above are true statements.

Question 57

The _______ is the part of the backbone that connects the LANs together.

A)Access layer
B)Distribution layer
C)Core layer
D)Privacy layer
E)Switched layer

Question 58

Computers can be assigned to a VLAN based on the ________.

A)IEEE 802.1q standard
B)NIC interface
C)physical port on the switch
D)IEEE 802.3 standard
E)physical location of the computer

Question 59

Most backbone devices are store-and-forward devices.One simple way to improve performance is to ensure that they have ________________.

A)enough ports
B)sufficient memory
C)twisted pair connections
D)large wheels
E)IEEE 802.11

Question 60

VLANs prioritize traffic based on the ______.

A)IEEE 802.1q standard
B)IEEE 802.11 standard
C)VLAN size
D)multiswitch allocation
E)switch dynamics

Question 61

List and describe five managerial factors to consider when selecting best practices for a backbone network design.

Question 62

Given network devices such as routers and switches, discuss three major technological trends that are helpful in explaining the differences between these devices.

Question 63

What are the main benefits of Virtual LANs?

Question 64

What are six actions that you might undertake as a network manager to improve backbone performance?

Question 65

When might a router be useful than a switch?

Question 66

Even though the access layer isn't part of the backbone, why is it important to the backbone?

Question 67

What are some business trends we are seeing in backbone networks?

Question 68

Describe how a VLAN works.