Ch8 Flashcards
A backbone network is a high-speed network that connects many networks.
T
Backbone networks typically use lower speed circuits to interconnect a series of
LANs and provide connections to other backbone networks.
F
A backbone network that connects many backbone networks spanning several
buildings at a single location is often called an Internet backbone.
F. Campus backbone or Enterprise backbone
The distribution layer of a backbone connects LANs together.
T
One basic component of a backbone network is the hardware device that connects
other networks to the backbone
T. and network cable
Which cable type is often used in backbone networks to provide higher data rates?
a) Coaxial cable
b) Twisted-pair cable
c) Fiber optic cable
d) Ethernet cable
C.
What are the basic components of a backbone network?
a) Network cables and access points
b) Routers and switches
c) Servers and computers
d) Network cables and hardware devices
D
Which hardware devices are used in backbone networks to transfer messages between different networks?
a) Computers only
b) Routers and VLAN switches
c) Switches and access points
d) Modems and gateways
B
At which layer of the OSI model do switches operate?
a) Transport layer
b) Data link layer
c) Network layer
d) Physical layer
B
What function do routers perform in a network?
a) They connect two different TCP/IP subnets
b) They operate at the physical layer of the OSI model
c) They learn addresses by reading source and destination addresses
d) They forward packets between network segments
A
Which layer of networks contains LANs that directly connect user devices like desktop PCs?
a) Core layer
b) Distribution layer
c) Access layer
d) Backbone layer
C
What is the function of the distribution layer in network architecture?
a) To connect different buildings on an enterprise campus
b) To connect access LANs within a building
c) To connect user devices directly
d) To manage network security
B
In which layer of networks are backbone networks found that connect different buildings on an enterprise campus?
a) Access layer
b) Distribution layer
c) Core layer
d) Peripheral layer
C
What is the commonality between backbone networks in the distribution and core layers?
a) They both connect user devices directly
b) They both operate by the backbone networks
c) They both manage network security
d) They both serve to interconnect networks
B
How does the function of the network cable in backbone networks compare to its function in LANs?
a) It serves the same purpose in both backbone networks and LANs
b) It operates at a different layer of the OSI model in backbone networks
c) It is used for different types of devices in backbone networks
d) It has a higher data transmission capacity in backbone networks
A
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
A
Switches and routers are devices that can connect networks to the BN.
T
The cable to connect BNs is usually twisted pair.
F
A hardware device that operates at the application layer is a router.
F. at the network layer
What is a characteristic of Layer-2 switches?
a) They modify messages as they pass through
b) They operate at the network layer
c) They are transparent devices
d) They primarily use IP addresses for forwarding packets
C
What role do Layer-2 switches play in message forwarding?
a) They analyze message content
b) They encrypt message data
c) They only read and forward messages
d) They prioritize message transmission based on content
C. They do not change messages. “ Transparent device”
Which addressing scheme do Layer-2 switches use to forward packets?
a) IP addresses
b) DNS addresses
c) MAC addresses
d) URL addresses
C
How do routers differ from Layer-2 switches in terms of message handling?
a) Routers forward all messages indiscriminately
b) Routers only forward messages that need to go to other networks
c) Routers do not process Layer-3 messages
d) Routers form new Layer-2 messages for outgoing packets
B
What distinguishes routers from switches in terms of message processing?
a) Routers perform less processing than switches
b) Routers do not process Layer-3 messages
c) Routers form new Layer-2 messages for outgoing packets
d) Routers process Layer-3 messages and perform more processing overall
D
What are VLAN switches primarily used for?
a) Connecting different buildings on an enterprise campus
b) Combining the features of Layer-2 switches and routers
c) Managing network security
d) Providing wireless access points
B
A switched backbone uses a bus topology
F. Star topology
. A __________ type of BN has a star topology with a switch at its center resulting in
all devices on the BN segment being part of the same IP network.
a. Bridged backbone
b. Virtual LAN
c. Hubbed backbone
d. Switched backbone
e. Routed backbone
D
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. switch the traffic based on layer 3 addresses
e. require much more management that do routed backbone networks
C
What is the most common type of backbone used mainly in the distribution layer?
A) Ring backbone
B) Switched backbone
C) Mesh backbone
D) Bus backbone
B
How are connections to the switch typically configured in a switched backbone?
A) Each connection is shared among multiple LANs.
B) Each connection is a separate point-to-point circuit.
C) Each connection is established using a mesh topology.
D) Each connection is established using a bus topology.
B
What is the result of having a star topology in a switched backbone?
A) Each LAN is connected to every other LAN.
B) Each LAN has its own dedicated circuit to the central switch.
C) Each LAN is connected in a circular arrangement.
D) Each LAN is connected to a common backbone cable.
B
In a switched backbone with a star topology, what is the implication for the devices on the backbone segment?
A) They are part of different IP networks.
B) They are not interconnected with each other.
C) They are all part of the same IP network.
D) They are connected using a mesh topology.
C
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).
T
Switched backbones place all network devices for one part of the building physically
in the same room, often in a rack of equipment
T
. 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.
A
With a switched backbone network, the equipment is usually placed in a ______.
a. server
b. NIC
c. cabinet
d. basement
e. rack
E
Devices in a rack are connected together using ___________.
a. patch cables
b. string
c. servers
d. modules
e. chassis switches
a
Devices in a rack are connected together using ___________.
a. patch cables
b. string
c. servers
d. modules
e. chassis switches
A
What is a benefit of using rack-mounted switched backbones?
A) Reduced network flexibility
B) Easier movement of computers among LANs
C) Increased likelihood of bottlenecks
D) Difficulty in offloading busy switches
B
When might rack-mounted switched backbones be particularly useful?
A) When there is no need to redistribute network traffic
B) When switches experience low traffic volume
C) When a busy switch requires offloading
D) When network cables converge into multiple locations
B
What potential issue can arise from concentrating high-traffic computers on a single switch?
A) Decreased network performance
B) Increased network flexibility
C) Enhanced network scalability
D) Improved switch efficiency
A
What does an MDF (Main Distribution Frame) setup allow in terms of network management?
A) It restricts cable convergence to multiple locations.
B) It prevents the redirection of cables from high-demand computers.
C) It allows all cables to converge into one location for efficient management.
D) It limits network traffic distribution to less busy switches.
C
How does the decoupling of network capacity from physical computer location affect network flexibility?
A) It restricts network flexibility by tying capacity to physical location.
B) It enhances network flexibility by allowing computers to connect to different network segments.
C) It reduces network flexibility by concentrating network traffic.
D) It has no effect on network flexibility
B
With switched backbones, network capacity is always tied to the physical location of
the computers.
F
How does the decoupling of network capacity from physical computer location affect network flexibility?
A) It restricts network flexibility by tying capacity to physical location.
B) It enhances network flexibility by allowing computers to connect to different network segments.
C) It reduces network flexibility by concentrating network traffic.
D) It has no effect on network flexibility
B
What is a characteristic of a chassis switch?
A) It only supports rack-mounted installations.
B) It allows users to plug modules directly into the switch.
C) It is limited to a fixed number of ports.
D) It requires separate switches for each network device.
B
What role do modules play in a chassis switch?
A) They regulate power distribution within the switch.
B) They determine the physical size of the switch.
C) Each module represents a specific type of network device.
D) They serve as the primary interface for users to interact with the switch.
C. One module might be a 16-port
100Base-T switch, another might be a router, whereas another might be a 4-port 1000Base-F switch, and
so on.
What determines the number and type of modules a chassis switch can hold?
A) The physical size of the switch
B) The availability of power sources
C) The internal capacity and design of the switch
D) The type of network devices connected to the switch
C
How does the flexibility of chassis switches benefit network expansion?
A) By reducing the number of available ports
B) By limiting the switch to specific technologies
C) By making it difficult to add new modules
D) By allowing easy addition of new modules with additional ports
D
What makes it simple to upgrade a chassis switch to use new technologies?
A) By reducing the number of modules
B) By increasing the complexity of the switch
C) By laying new cables and inserting appropriate modules into the chassis switch
D) By limiting the switch to existing technologies
C
A key advantage of a chassis switch is its flexibility
T
Where are routed backbones commonly used within enterprise campus networks?
A) At the access layer
B) At the distribution layer
C) At the core layer
D) At the aggregation layer
C
What is the primary function of routers in a routed backbone?
A) To connect LANs to switches
B) To break the network into separate subnets
C) To manage broadcast messages
D) To increase network speeds
B
How do routers handle message traffic in a routed backbone?
A) By transmitting packets at the data link layer (Layer 2)
B) By transmitting packets at the network layer (Layer 3)
C) By transmitting packets at the transport layer (Layer 4)
D) By transmitting packets at the physical layer (Layer 1)
B
What advantage does a routed backbone offer in terms of network efficiency?
A) It allows for faster network speeds compared to switching.
B) It limits broadcast messages to within one subnet.
C) It provides centralized management of subnet addresses.
D) It enables seamless communication between different buildings.
B
What is a disadvantage of using routers in a routed backbone compared to switches?
A) Routers require less management.
B) Routers are less costly than switches.
C) Routers result in slower speeds due to routing.
D) Routers have a lower impact on network efficiency.
C. compare to switch
Routers can only connect the same type of cable
F
. Routers connect two or more network segments that use the same or different data
link protocols, but the same network protocol.
T
One difference between a switch and a router is that a router will only process
messages addressed to the router (at layer 2), while a switch processes all messages.
T
- 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
T
One advantage of a routed backbone is that is requires little management.
F. require more management hand higher cost for routers than switches
Backbone networks are rarely used anymore.
F
Switched backbones are harder to maintain and upgrade than a BN that is not rackbased.
F
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.
D
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 switches do.
e. Routers can choose the “best” route between networks for forwarding a packet
A
What ensures that broadcast messages stay within their respective subnets in a routed backbone?
A) Core routers
B) Distribution layer switches
C) Access layer routers
D) Routers
D