Transmission Media

Question 1

what is broadband?

Answer 1

refers to any high-speed internet access that is always on and faster than traditional dial-up access

it has wide bandwidth data transmission which transports multiple signals and traffic types

Question 2

what is the name of the method of connecting to the internet?

Answer 2

Digital Subscriber Line (DSL)

Question 3

what is bandwidth?

Answer 3

its a measure of the capacity of a communication channel. it is the range of frequencies that a channel can handle

Question 4

what is transmission rates referred to?

Answer 4

line speed

Question 5

what are the types of twisted pair of wires called?

Answer 5

unshielded twisted pair (UTP)

shieled twisted pair (STP)

Question 6

what is UTP?

Answer 6

Unshielded Twisted Pair

its similar to STP, but has no earthed shield- in some cases they can be used for data transmission

UTP is a type of cable that consists of two independently insulated wires twisted around one another

Question 7

how is UTP connected?

Answer 7

one wire carries the signal while the other is only used to cancel out interference - e.g. electronic interference

Question 8

why twist UTP this way?

Answer 8

twisting it this way reduces signal loss over any given length of cable. the media allows for very high speed data transmission

the quality of the cable may vary from telephone grade wire to extremely high speed cable

Question 9

what are the advantages of UTP?

Answer 9

high transformation speeds

cheap costs of insulation

Question 10

what are disadvantages of UTP?

Answer 10

the cable can only be used over a short distance

cable may be susceptible to radio and electrical frequency interference

there are security concerns regarding the intercepting of data along transmission lines

Question 11

what is STP?

Answer 11

Shielded Twisted Pair

its similar but expect it has copper shielding around each pair of cables. this makes it suitable for environment where electric interference may be an issue

the shielding protects the data from corruption due to interference

Question 12

what is a coaxial cable?

Answer 12

same kind of cable used for connecting a TV arial to a TV

Question 13

what are the two of conductors in a coaxial cable?

Answer 13

one is wire down the centre of the cable, which is made of a single strand

the other is insulated by many strands braided around insulation for the inner wire

Question 14

what is the advantage of having an outer shield?

Answer 14

it protects against interference

very fast transmission speeds

cheap to purchase

Question 15

what is disadvantage of having outer shield?

Answer 15

it being the only capable for short distance communication

it is physically inflexible

Question 16

what type of cable consists in fibre optic?

Answer 16

very fine glass strands that allow rapid transmission of data, using modulated beams

Question 17

what does fibre optic do ?

Answer 17

it provides interference free, secure data transmission and unlike metal wires it not subject to corrosion

multiple strands are placed together in a single cable, each on capable of carrying one or more data signals

fiber optic used for very high speed, long distance data transmission and is not a subject to electrical interference

Question 18

how is fibre optic wires protected?

Answer 18

the fine glass strands are surrounded by cladding layer and jacket. cladding is an insulated material and jacket with a protective covering

Question 19

why is their two fibers in fiber optic?

Answer 19

one for sending and one recieving

fibers are undirectional

Question 20

how does data travel in fiber optic?

Answer 20

it has the ability to transmit signals over much longer distances than coaxial and twisted pair

the data is transmitted as a series of pulses of light along thin fibers whereby each fiber can tansmit in one direction

Question 21

advantages of fiber optic

Answer 21

greater bandwidth than metal cables, which means it has a bigger data capacity

less susceptible than metal cables to interference

data can be transmitted in digital form

data can travl in a secure way, impossible for hackersto intercept data

Question 22

disadvantages of fiber optic

Answer 22

its expensive to install

Question 23

what is wireless?

Answer 23

it cover a range of possible methods of data transmission, which can be used for linking computers

Question 24

what is bluetooth?

Answer 24

its a short range wireless communications standard that uses low-power radio waves

it allows bluetooth equipped devices to communication with other bluetooth devices in a peer-to-peer relationship

Question 25

what do bluetooth and wifil have in common?

Answer 25

standards continue to improve

speeds up transfer times

reducing power use

Question 26

what is wifi?

Answer 26

wifi is a communication technology that makes use of radio waves in order to connect to a local area network

its a way of connecting computers to a network by wireless via radio waves

Question 27

how does wifi transfer from computer to a mobile phone?

Answer 27

both must be connected to the same router. file sharing must be enabled on both the computer and device. the computer will display the devices on the network. the mobile device will be selected. then the data will be transferred via router

Question 28

twisted pair bandwidth and security?

Answer 28

low bandwidth

low security

Question 29

coaxial bandwidth and security?

Answer 29

moderately high bandwidth

fair security

Question 30

fiber optic bandwidth and security?

Answer 30

very high bandwidth

high security

Question 31

wifi bandwidth and security?

Answer 31

high bandwidth

low security

Question 32

how does bluetooth transfer data from computer to device?

Answer 32

both bluetooth must be enabled. the computer will display the devices within range which are set to visible. the mobile device will be selected. the device may require pairing. a piconet is created

Question 33

fibre optic and mental wire in relation to data security

Answer 33

fibre optic consists of many strands of glass fibres inside an insulated casing. data is transported using pulses of light. data security- its not prone to interception. its less susceptible to interception than metal cable

metal copper wire are used to transmit electrical signals. the wires are encased by an insulating layer- data security- it can be tapped into using listening devices wrapped round it which doesn’t interfere with the signal