Data Communications - Ch 8
A backbone network that connects many backbone networks spanning several buildings at a single location is often called an Internet backbone.
False
A hardware device that operates at the application layer is a router.
False
Backbone networks typically use lower speed circuits to interconnect a series of LANs and provide connections to other backbone networks.
False
Layer-3 switches switch messages based only on their data link layer address.
False
One advantage of a routed backbone is that is requires little management.
False
Routers can only connect the same type of cable.
False
Routers connect two or more network segments that use the same or different data link protocols, but the same network protocol.
True
Switches and routers are devices that can connect networks to the BN.
True
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.
True
Routers: 1. connect different IP networks or subnetworks 2. typically do not require any configuration by the network administrator 3. use data link layer addresses to move packets that leave the subnet 4. typically require only one TCP/IP address 5. do less processing on packets than a layer 2 switch does
1
Switches: 1. learn addresses by reading the source and destination addresses 2. operate at the physical layer only 3. connect two ore more network segments that use different data link protocols 4. connect two or more network segments that use different network protocols 5. have become less popular than hubs
1
Which of the following is true regarding switched backbones? 1. They place all network devices for one part of the building physically in the same room, often in a rack of equipment 2. They have an advantage of requiring less cable 3. They make it more difficult to move computers from one LAN to another 4. Network capacity is always tied to the physical location of the computers 5. They are harder to maintain and upgrade than a BN that is not rack-based
1
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. 1. Bridged backbone 2. Virtual LAN 3. Hubbed backbone 4. Collapsed backbone 5. Routed backbone
2
Which of the following is not a technology layer that is considered when designing backbone networks? 1. access layer 2. distribution layer 3. decentralized layer 4. core layer 5. none of the options
3
Which of the following is not a type of hardware device that can be used to interconnect networks? 1. layer 3 switches 2. routers 3. dumb terminals 4. layer 2 switches 5. all of the above can be used
3
Which of the following is not true about switched backbones? 1. network latency (delay) is decreased in comparison to traditional (bridged or routed) backbone networks 2. each connection into the switch is a separate point-to-point circuit which supports simultaneous access by the LANs connected to the switch 3. there are many more networking devices in a switched backbone network compared to the number of LANs attaching to it 4. use a star topology 5. the backbone essentially exists in the switch; there is no backbone cable
3
Which of the following would be least effective in improving backbone performance? 1. upgrading memory for devices in the network 2. changing the demand placed on the network 3. adding new keyboards to the client computers 4. upgrading the circuits between devices 5. improving devices in the network
3
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. 1. Bridged backbone 2. Virtual LAN 3. Hubbed backbone 4. Switched backbone 5. Routed backbone
4
Routers: 1. operate at the application layer 2. operate only at the physical layer 3. cannot connect two or more networks that use the same type of cable 4. may also be called TCP/IP gateways 5. operate only at the data link layer
4
A subnetted or hierarchical backbone can also be called: 1. Bridged backbone 2. Virtual LAN 3. Hubbed backbone 4. Collapsed backbone 5. Routed backbone
5
Which of the following is not true about backbone networks? 1. They may also be called enterprise networks if they connect all networks within an organization. 2. They typically connect many networks, including LANs. 3. They typically provide connections to other BNs, WANs, MANs, and the Internet. 4. They may also be called campus networks if they connect many BNs spanning several buildings as a single location. 5. They tend to use lower speed circuits than LANs.
5
A VLAN network assigns computers to LAN segments by hardware.
False
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.
False
A backbone network is a high-speed network that connects many networks
True
A room that contains a rack of equipment for a rack-based backbone is also called the main distribution facility (MDF) or central distribution facility (CDF).
True
