quis chapter 4 CCNA

1. A network team is comparing topologies for connecting on a shared media. Which physical topology is an example of a hybrid topology for a LAN?
extended star *
Refer to curriculum topic: 4.4.3
An extended star topology is an example of a hybrid topology as additional switches are interconnected with other star topologies. A partial mesh topology is a common hybrid WAN topology. The bus and ring are not hybrid topology types.


2. Refer to the exhibit. One end of the cable is terminated as displayed, and the other end is terminated in accordance with the T568A standard. What type of cable would be created in this manner?
straight-trough *
Refer to curriculum topic: 4.2.2
A straight-through cable can have either a T568A or T568B standard termination at one end and the same at the other end. A crossover cable has a T568A standard termination at one end and a T568B standard at the other end. A rollover cable can have either a T568A or T568B standard termination at one end, and at the other end have the same standard, but with the wires connected in reverse order. A fiber-optic cable is not terminated using RJ-45 connectors.

3. Which method of data transfer allows information to be sent and received at the same time?
  full duplex *
Refer to curriculum topic: 4.4.3

4. Match the description with the media. (Not all options are used.)
STP - This type of copper media is used in industrial or similar environment
wireless - This type of media provides the most mobility options
optical fiber - media is used for high transmission speed and can also transfer data over long distances
caoxial - Traditionally used for television but can now be used in a network
Other Incorrect Match Options:
This type of media is used in wired office environments.
Refer to curriculum topic: 4.2.1
UTP cables are used in wired office environments. Coaxial cables are used to connect cable modems and televisions. Fiber optics are used for high transmission speeds and to transfer data over long distances. STP cables are used in environments where there is a lot of interference.

5. Refer to the exhibit. What is the maximum possible throughput between the PC and the server?
  128 kb/s *
 Refer to curriculum topic: 4.1.3
The maximum throughput between any two nodes on a network is determined by the slowest link between those nodes.


6. Which is a function of the Logical Link Control (LLC) sublayer?
to identify which network layer protocol is being used *
Refer to curriculum topic: 4.3.1
Defining the media access processes that are performed by the hardware and providing data link layer addressing are functions of the MAC sublayer. The data link layer accepts Layer 3 packets and packages them into data units that are called frames.


7. Match each type of frame field to its function. (Not all options are used.)
addressing  - this field helps to direct the frame toward its destination
error detection - this field check if the frame has been damaged during the transfer
type - used by the LLC to identify the layer 3 protocol
Other Incorrect Match Options:
This field identifies special flow control services.
Refer to curriculum topic: 4.4.4
Place in the following order:
error detection - This field checks if the frame has been damaged during the transfer.
The second answer is not used.
addressing - This field helps to direct the frame toward its destination.
frame start - This field identifies the beginning of a frame.
type - This field is used by the LLC to identify the Layer 3 protocol.


8. Fill in the blank.
In fiber optic media, the signals are represented as patterns of
Light
Refer to curriculum topic: 4.1.2
In fiber optic media, the physical layer produces the representation and groupings of bits as patterns of light.


9. Which two factors influence the method that is used for media access control? (Choose two.)
how the connection between nodes appears to the data link layer *
how nodes share the media  *
Refer to curriculum topic: 4.4.1
The media access control method used depends on the topology (how the connection between the nodes appears to the data link layer), and how the nodes share the media. The type of data generated by end devices applications, the way signals are encoded by the NICs on end devices, and even the way the IP protocol forwards the packet through the network have no influence on the choice of the method used for media access control.


10. What is a characteristic of a WAN hub-and-spoke topology?
The branch sites are connected to a central site through point-to-point links.? *
Refer to curriculum topic: 4.4.2
A hub-and-spoke topology is a WAN version of the star topology in which a central site interconnects branch sites using point-to-point links. A mesh topology requires that every end system be interconnected to every other system using point-to-point links. A partial mesh is a variation of this topology, where some but not all end devices are interconnected. There is no topology where all the sites have to have hub devices that are connected to a router.


11. Which statement correctly describes frame encoding?
It converts bits into a predefined code in order to provide a predictable pattern to help distinguish data bits from control bits. *
Refer to curriculum topic: 4.1.3
Frame encoding converts a stream of data bits into a predefined code that is recognized by both the sender and receiver. These codes are used for a variety of purposes, such as distinguishing data bits from control bits, and identifying the beginning and end of a frame.


12. Which statement describes a characteristic of the frame header fields of the data link layer?
They vary depending on protocols. *
Refer to curriculum topic: 4.4.4
All data link layer protocols encapsulate the Layer 3 PDU within the data field of the frame. However, the structure of the frame and the fields that are contained in the header vary according to the protocol. Different data link layer protocols may use different fields, like priority/quality of service, logical connection control, physical link control, flow control, and congestion control.

13. What type of cable is used to connect a workstation serial port to a Cisco router console port?
rollover  *
Refer to curriculum topic: 4.2.2
UTP cable wire pairs can be terminated in different configurations for use in different applications. To use a UTP cable for consoling into a Cisco router from a PC serial port, it must be terminated as a rollover or console cable.


14. What method is used to manage contention-based access on a wireless network?
CSMA / CA *
Refer to curriculum topic: 4.2.4
Carrier sense multiple access with collision avoidance (CSMA/CA) is used with wireless networking technology to mediate media contention. Carrier sense multiple access with collision detection (CSMA/CD) is used with wired Ethernet technology to mediate media contention. Priority ordering and token passing are not used (or not a method) for media access control.

15. What is the purpose of the OSI physical layer?
transmitting bits across the local media *
Refer to curriculum topic: 4.1.2
The physical layer is responsible for transmitting the actual signals across the physical media as bits. Exchanging frames, controlling media access, and performing error detection are all functions of the data link layer.

 16. What makes fiber preferable to copper cabling for interconnecting buildings? (Choose three.)
  greater distances per cable run  *
imited susceptibility to EMI/RFI  *
 greater bandwidth potential  *

Refer to curriculum topic: 4.2.3

 17. A network administrator is designing a new network infrastructure that includes both wired and wireless connectivity. Under which situation would a wireless connection be recommended?
The end-user device needs mobility when connecting to the network. *
Refer to curriculum topic: 4.1.1
When the end-user devices need mobility to connect to the network, wireless is recommended. If an end-user device only has an Ethernet NIC, the user will only be able to use Ethernet cabling. If RFI is an issue, wireless is not recommended. An end-user device that requires a dedicated connection for performance would perform better with a dedicated Ethernet cable.