Considered the future of worldwide telecommunications, fibre optic cables transmit data using pulses of light rather than electrical signals, unlike traditional copper wiring. Fibre optic cables do so through a phenomenon called total internal reflection. Fibre optic cables comprise transparent, thin glass or plastic fibres surrounded by cladding -- or a glass sheath -- and a protective buffer coating. Though having largely replaced copper cables in commercial applications, ultra-high-speed fibre-to-the-home installations are still a far-off dream for the majority of the domestic sector.
Bandwidth Capacity and Speed
Even the most advanced copper cables carry just a fraction of the information a fibre optic cable can carry. The latter's use of optically based signals gives it far greater data capacity than cables dependent on electrically based signals, allowing it to attain incredible throughput speeds. As of May 2011, current fibre optic technology allows transmissions as fast as one terabyte per second in a single fibre, while the maximum for copper cables rests at one gigabyte per second, and an even lower rate of 50 megabytes per second for DSL's twisted copper pairs. Optical fibres of the future are expected to carry as much as 350 terabytes per second.
Low signal attenuation, another very strong point in favour of a fibre optic cable, results from its virtual immunity to electromagnetic interference, giving it an extremely low error rate. Optical fibres' excellent electrical resistance makes their instalment near high-voltage cables -- and between areas with varying earth potentials -- safe. This incredibly low signal degradation allows information to travel longer distances -- more than 124 miles, compared to copper cables' limit of 3 miles -- without the necessity of regeneration. Eliminating this necessity means less power consumed for signal transmission and therefore, greater cost-efficiency in the end.
In terms of manufacturing costs, optical fibres are cheaper than copper wiring; however, fibre optic systems remain largely unfeasible for home use, as average instalment costs per fibre subscriber stand at around £650 as of 2011. These racked-up costs result from expensive, specialised test equipment including reflectometers -- which measure electrical power -- and optical probes. The prohibitive cost of a fibre optic cable set-up makes the more affordable DSL technology a more reasonable home option; therefore, while optical networks are practical for carrier network backbones and for industries requiring high-speed telecommunication, DSL remains the best choice for subscriber and end-user access.
Limited Physical Strength
Regarding size and weight, optical fibres have a significant edge over copper cables, with a mile of each weighing about 9.98 Kilogram and 1633 Kilogram, respectively. While this generally makes for easier handling, the fragile nature of fibre optic cables makes their installation a delicate process. Bending, tugging, twisting, and pulling result in the loss of some light-reflecting properties, and must be minimised. Aside from their higher susceptibility to damage contrasted with copper cables, the complexity -- and therefore the cost -- of repairs for optical networks is greater.
- 20 of the funniest online reviews ever
- 14 Biggest lies people tell in online dating sites
- Hilarious things Google thinks you're trying to search for