ITEC45 (Sir Rollo)

Question 1

The physical means by which data is transmitted from one
geographic or electronic location to another

Answer 1

transmission, or “communication” media.

Question 2

physical path between the transmitter and the receiver.

Answer 2

transmission medium

Question 3

all other factors remaining constant, the greater the
bandwidth of a signal, the higher the data rate that
can be achieved.

Answer 3

bandwith

Question 4

impairments, such as attenuation, limit the distance.

Answer 4

Transmission Impairments

Question 5

is particular concern for unguided media, but is also a problem with guided media.

Answer 5

Interference

Question 6

A guided medium can be used to construct a
point to-point link or a shared link with multiple
attachments.

Answer 6

Number of receivers

Question 7

referred to as Wired or Bounded transmission
media.

are physical cables that signals travel through
on a narrow path.

• are made up of an external conductor (usually
  copper) wrapped in a jacket made of
  nonconductive material.

Answer 7

Guided Media or Bounded

Question 8

includes telephony, telegraphy, and television, means communication at a distance

Answer 8

Telecommunication

Question 9

refers to information presented in whatever form is agreed upon by the parties creating and using the data.

Answer 9

data

Question 10

are the exchange of data between two devices via some form of transmission medium such as a wire cable

Answer 10

Data Communication

Question 11

The system must deliver data to the correct destination. Data must be received by the intended device or user and only by that device or user.

Answer 11

Delivery

Question 12

The system must deliver the data accurately. Data that have been altered in transmission and left uncorrected are unusable.

Answer 12

Accuracy

Question 13

The system must deliver data in a timely manner. Data delivered late are useless. In the case of video and audio, timely delivery means delivering data as they are produced, in the same order that they are produced, and without significant delay. This kind of delivery is called real-time transmission.

Answer 13

Timeliness

Question 14

refers to the variation in the packet arrival time. It is the uneven delay in the delivery of audio or video packets.

Answer 14

Jitter

Question 15

is one of the most commonly used modes of communication now a days.

is a mode of communication where the information or the thought is encoded digitally as discrete signals and electronically transferred to the recipients.

Answer 15

Digital Communication

Question 16

is the transmission of digital pulses between two or more points in a communication system.

Answer 16

Digital transmission

Question 17

is the transmitted of digital modulated analog carriers between two or more points in a communication system.

Answer 17

Digital radio

Question 18

This sequence of binary digits is called

Answer 18

information sequence.

Question 19

the process of efficiently converting the output of whether analog or digital source into a sequence of binary digits is known as

Answer 19

Source Encoding or Data Compression

Question 20

is to introduced, in controlled manner, some redundancy in the binary information sequence that can be used at the receiver to overcome the effects of noise and interference encountered in the transmission on the signal through the channel.

Answer 20

Channel Encoder

Question 21

convert the sequence into electric signals so that we can transmit them on channel

maps the binary sequences into signal wave forms , for example if we represent 1 by sin x and 0 by cos x then we will transmit sin x for 1 and cos x for 0. ( a case similar to BPSK)

Answer 21

Digital Modulator

Question 22

is the physical medium that is used for transmitting signals from transmitter to receiver.

Answer 22

Channel

Question 23

processes the channel corrupted transmitted waveform and reduces the waveform to the sequence of numbers that represents estimates of the transmitted data symbols.

Answer 23

Digital Demodulator

Question 24

tries to decode the sequence from the knowledge of the encoding algorithm. And which results in the approximate replica of the input at the transmitter end.

Answer 24

Source Decoder

Question 25

Finally we get the desired signal in desired format analog or digital.

Answer 25

Output Transducer

Question 26

is the information (data) to be communicated. Popular forms of information include text, numbers, pictures, audio, and video.

Answer 26

Message

Question 27

is the device that sends the data message. It can be a computer, workstation, telephone handset, video camera, and so on

Answer 27

Sender

Question 28

is the device that receives the message. It can be a computer, workstation, telephone handset, television, and so on.

Answer 28

receiver

Question 29

is a set of rules that govern data communications. It represents an agreement between the communicating devices. Without a protocol, two devices may be connected but not communicating, just as a person speaking French cannot be understood by a person who speaks only Japanese.

Answer 29

protocol

Question 30

is an electrical or electromagnetic current that is used for carrying data from one device to another

Answer 30

Signal

Question 31

are in continuous wave form in nature and represented by continuous electromagnetic waves

Answer 31

Analog Signal

Question 32

are discrete in nature and represent sequence of voltage pulses. are used within the circuitry of a computer system.

Answer 32

Digital Signal

Question 33

This method is used to send computer information over transmission channels that require analog signals, like a fiber optic networks, computer modems, cellular phone networks, and satellite systems. In each of this systems, an electromagnetic carrier wave is used to carry the information over great distances and connect digital information users at remote locations.

Answer 33

Digital Data with Analog Signals

Question 34

A digital signal can be transmitted over a dedicated connection between two or more users. In order to transmit analog data, it must first be converted into a digital form. This process is called sampling, or encoding.

Answer 34

Analog Data with Digital Signals

Question 35

is a collection of zeroes and ones, where the value at any one time is called a bit

Answer 35

digital data

Question 36

It is communication path through which data or information can be send from one node to another node.

Answer 36

Channel

Question 37

Maximum rate at which data can be transmitted over a communication path or channel is called

Answer 37

Channel Capacity

Question 38

is named after the two conductors that run parallel to each other. - the center conductor in the cable is usually copper, which is usually either a solid wire or stranded, twisted copper Cable TVs and analog television networks widely use this. - has an inner conductor surrounded by a tubular insulating layer, surrounded by a tubular conducting shield. Many coaxial cables also have an insulating outer sheath or jacket

Answer 38

coaxial cable

Question 39

-dedicated cable bandwidth - use digital signaling over a single wire -is bidirectional, allowing computers to both send and receive data using a single cable. - the sending and receiving cannot occur on the same wire at the same time

Answer 39

Baseband mode

Question 40

uses digital signaling, broadband uses analog signals in the form of optical or electromagnetic waves over multiple transmission frequencies -for signals to be both sent and received, the transmission media must be split into two channels. - two cables can be used: one to send and one to receive transmissions.

Answer 40

Broadband mode

Question 41

it consists of two separately insulated conductor wires wound about each other. Generally, several such pairs are bundled together in a protective sheath. -is made of pairs of solid or stranded copper twisted along each other

Answer 41

Twisted Pair

Question 42

is the unintentional transfer of signals from one channel to another channel, creating interference.

Answer 42

crosstalk

Question 43

type of cable has the ability to block interference and does not depend on a physical shield for this purpose

Answer 43

Unshielded twisted-pair (UTP)

Question 44

-type of cable consists of a special jacket to block external interference - It is used in fast-data-rate Ethernet and in voice and data channels of telephone lines.

Answer 44

Shielded twisted-pair (STP)

Question 45

-It uses the concept of reflection of light through a core made up of glass or plastic. =It is used for transmission of large volumes of data.

Answer 45

Optical Fibre

Question 46

Has a larger core diameter that lets multiple modes of light propagate - The amount of light reflections increase as they travel through the core, which allows more data to pass through

Answer 46

Multi Mode Cables

Question 47

-It is also referred to as Wireless or Unbounded transmission media. - No physical medium is required for the transmission of electromagnetic signals

Answer 47

Unguided Media or Unbounded

Question 48

is to provide the rules and regulations that allow computers with different disk operating systems, languages, cabling and locations to share resources.

Answer 48

Data Communication

Question 49

is defined as the rate of transference of error ­free data. it is measured by the response time.

Answer 49

performance

Question 50

is the elapsed time between the end of an inquiry and the beginning of a response

Answer 50

response time

Question 51

the speed that the data will be transmitted at measured in bits per second (bps).

Answer 51

Transmission Speed

Question 52

the type of physical connection used to connect nodes together.

Answer 52

Media Type

Question 53

is the predictability of response time and accuracy of data.

Answer 53

consistency

Question 54

is the measure of how often a network is usable.

Answer 54

Reliability

Question 55

is a measure of the average time a component is expected to operate between failures, and is normally provided by the manufacturer.

Answer 55

MTBF (Mean Time between Failures)

Question 56

is the network's ability to return to a prescribed level of operation after a network failure.

Answer 56

Recovery

Question 57

is the protection of hardware, software and data from unauthorized access.

Answer 57

security

Question 58

the transmitter of data. the starting point of the data.

Answer 58

Source

Question 59

The communications stream through which the data is being transmitted.

Answer 59

Medium

Question 60

the interface between the source and the medium, and the medium and the receiver. are a physical piece of equipment. refers to computer hardware devices used to establish, maintain and terminate communication network sessions between a data source and its destination.

Answer 60

DCE (Data Communication Equipment)

Question 61

is the telecommunications name given to the source and receiver’s equipment. also be called tail circuits. is an end instrument that converts user information into signals or reconverts received signals. DTE (Data Terminal Equipment)

Answer 61

DTE (Data Terminal Equipment)

Question 62

This includes storage and retrieval of information, reducing the need for paper traffic and record keeping in paper format, as well as rationalizing the time that staff spends producing correspondence and accounts.

Answer 62

Business

Question 63

it is standard procedure to use networks to share data and use remote computers to carry out large computations

Answer 63

Scientific Use

Question 64

defines the direction of signal flow between two connected devices. also known as communication mode. means transferring of data between two devices

Answer 64

Transmission Modes

Question 65

is the process of sending data one bit at a time, sequentially, over a communication channel or computer bus Bit serial transmission is necessary in data communications if only a single channel is available. one channel will pass only one bit at a time.

Answer 65

Serial communications

Question 66

is a method of sending several data signals simultaneously over a transmission link at one time. it comprises of several wired channels in parallel. there is a onetime transfer of data from source to destination.

Answer 66

Parallel communications

Question 67

the communication is unidirectional, as on a one-way street. Only one of the two devices on a link can transmit, the other can only receive. the simplex mode can use the entire capacity of the channel to send data in one direction. it is rarely used for data communication.

Answer 67

Simplex Mode

Question 68

is used in cases where there is no need for communication in both direction at the same time. can alternately send and receive data but not at the same time. When one device is sending, the other can only receive, and vice versa

Answer 68

Half­ Duplex Mode

Question 69

both stations can transmit and receive simultaneously. signals going in one direction share the capacity of the link with signals going in other direction. is used when communication in both direction is required all the time.

Answer 69

Full Duplex Mode