If you are on the cusp of making a difficult decision regarding getting a fibre optic connection, you may have questions regarding its advantages and disadvantages, or whether it is hard to design and install a fibre network. The following brief guide is aimed at answering these essential questions.
- Brief introduction
Fibre is not a new invention – the first fibre optic link was installed as early as 1976 in Chicago. It has replaced over 90% of all the voice circuits for long-distance communication and chances are that if you make a long-distance call today, you are talking over fibre optics. Large office buildings have fibre in their buildings and the installation of fibre to the home is increasingly popular. The back-end of mainframes and storage area networks (SANs) are almost totally fibre.
Fibre is certainly the medium of choice for long distance, high bandwidth or secure communications. A major advantage of fibre is its unequalled level of security since it cannot be jammed or tapped and is resistant to interference. This advantage is seated in the physics of transmitting data via photons instead of electrons. Fibre, using flexible and transparent glass or plastic drawn to a diameter slightly thicker than that of a human hair, has much less attenuation than that of electrical signals in copper and is less dependent on signal frequency. Fibre optic transmission neither radiates radio-frequency interference (RFI) nor is it susceptible to interference. Utility companies can run power lines with fibres embedded in the wires for both communications and network management. Single mode fibre offers almost unlimited bandwidth, especially with DWDM (dense wavelength division multiplexing) which is a convincing argument to switch to fibre.
The economics of copper versus fibre and the design of fibre networks relate to the availability of options for upgradeability in the future. This is evident considering that commercial systems currently carry more phone conversations compared to copper pairs that may run hundreds of kilometres between all-optical repeaters. Aspects such as material costs, installation and splicing labour, and reliability are in fibre’s favour.
- Understanding Fibre Optic Communications
The pathways between devices consist of bidirectional signals transmitted in two directions on two differentfibre optic links. Using two fibres is the cheapest way, since the optical fibre itself is very affordable. As with a copper wire, the link has a transmitter that converts electronic signals into optics and a receiver that converts the signal back to electronics and thus connects signals from two devices.
Light-emitting diodes (LED), or photo diodes are light emitters and are a key element in a fibre optic system. This component converts the electrical signal into a corresponding light signal that can be injected into the fibre. Semiconductor lasers convert electronic signals into optical signals and transmit in the infrared region which is beyond human perception. Slower links reach speeds of about 100 million bits per second (Mb/s). Faster links use infrared semiconductor lasers because they have more bandwidth reaching speeds of up to tens of billions of bits per second (Gb/s).