3f Optical Communication *** Flashcards Preview

ICT A Level > 3f Optical Communication *** > Flashcards

Flashcards in 3f Optical Communication *** Deck (3):

Describe three disadvantages of using fibre optic cable to connect two buildings for a small business. (6 marks)

One mark for point, one for expansion eg:
 cost of cable is more expensive (1) compared to wire
media (1)
 network portion needs to be down (1) if new nodes are to
be spliced in (1)
 breakage/damage to cable (1) entire cable needs re-laying
 initial set up cost (1) electronic signals require conversion
(1) by a source and a receiver (1) at both ends of
transmission (1)
 optical regenerators/laser amplifiers needed (1) impurities
in the glass and the wavelength used cause the signal to
degrade over large distances (1)
 physical disruption (1) if cable needs to be housed
underground (1).
Max two points per disadvantage


Describe three advantages for the wedding outfitter of using fibre optic cable to connect the two buildings. (6 marks)

 greater capacity (1) more data can be exchanged
simultaneously (1)
 transmission rates (1) higher volume of data per second (1)
 less signal degradation (1) data can travel greater distances
without amplification (1)
 not susceptible to electrical interference (1) better quality of
data transmission/less errors (1)
 security (1) less difficult to tap in to (1) doesn’t leak light (1)
 carries digital signals (1) no need for signal conversion (1) [6]


Describe three disadvantages, for the business, of using lasers to connect the LANs in the
salons together. (6 marks)

 direct line-of-sight required (1) laser beam cannot be bent
around any intervening building / obstacle (1)
 atmospheric changes (e.g rain, smoke and fog) (1) can affect
quality of signal (1)
 both ends of communication need the hardware (1) the cost
of set up can be inhibiting (1)

Decks in ICT A Level Class (54):