What is Fibre Optics?

An optical fibre is a thin glass strand that carries light along its length. Light from lasers is shone down the fibre, and is detected by a receiver at the other end of the fibre. Due to their special design, the light within the fibre does not escape out of the sides of fibre (called total internal reflection) and the loss of the light is very low over the fibre length. Because they don’t conduct electricity and lightning, optical fibre cables can be a lot safer than electrical cables because there’s never a risk of receiving a shock. They are also immune from electrical interference caused by heavy industry or other appliances in the home.

Optical Fibre vs Copper Wires

Just as broadband consumers in other parts of the world have found, we don’t expect the copper network to meet the future demands for bandwidth that NZ households and businesses will require. Optical fibre is a logical choice for ‘future-proofing’ the network as the need for higher speeds and usage continue to grow over time. Optical fibre is capable of transmitting information at a practically unlimited rate over long distances of tens of km’s. The kind of optical fibre services to be deployed will assure speeds of 100 Mbps and higher, that’s 100 million bits per second – and order of magnitude greater than the broadband speeds most New Zealander’s currently receive on their old copper cables.

Network Topology – Passive Optical Network (PON)

The preferred solution world-wide for fibre networks to households is to deploy a ‘shared’ fibre service known as a Passive Optical Network (PON). The electrical equipment to ‘drive’ the optical fibre, including lasers, consumes power. This equipment is located in a central location, a Fibre Access Node (or FAN), and within the Optical Network Terminal unit at each home. A PON uses small dedicated optical fibre runs from the home to a small cabinet in the street, known as a Fibre Distribution Hub (FDH). In this cabinet the individual fibres from a small number of homes (normally less than 32 homes) are combined together into a single fibre back to the central equipment. The PON therefore uses fewer lasers at the central equipment, and also significantly fewer fibres. As a result, the PON uses less power than dedicated fibre

Reduces the cost of network deployment

Current PON technologies, such as Gigabit PON (GPON) support speeds of up to 100Mbps per household, or higher if fewer homes are connected to the PON. This speed is achievable at distances of up to 15km from the central exchange. These longer distances mean that fewer ‘exchanges’ will be needed compared to traditional copper-based telecommunication services. Optical fibre is also suitable for large business, schools, universities and research organisations, hospitals and for corporate users. Fibre is already used extensively for some of these purposes today and will be put to even greater use in the future. For institutions that have the highest information requirements, dedicated ‘point-to-point’ fibre services will continue to be available and deployed.

Optical Fibre and the Home

Unlike copper-based telecommunications, optical fibre does not have the ability to carry a voltage or power down the line. In addition, optical fibre services support a wide range of applications – telephony, Internet, TV – which all have different connector types. In order to deliver these connectors and to provide power to the devices connected (eg. ringing the telephone) the optical fibre requires a special network termination unit to be attached. This device is called an Optical Network Termination (ONT), and it requires power to be supplied to it – much in the same way a DSL modem requires power today.

Why do we need all that bandwidth?

all you want to do is surf web pages, download a few songs, send and receive some photographs, or watch streaming video at current picture quality levels, then the bandwidth provided by today’s cable modems and DSL services is probably good enough for you. But the world is moving toward vastly higher bandwidth applications. Companies like Netflix, Amazon and Wal Mart are offering feature-length movies for download. More people are looking to upload their own home movies into emails or web pages. Consumer electronics companies are coming out with devices that connect televisions to the Internet. High-definition video is fast becoming the state-of-the-art, and one high definition movie takes up as much bandwidth as 35,000 web pages. In the meantime, a growing number of companies are offering “software as service” – meaning you subscribe to applications on the net rather than install them on your own computer. These “cloud computing” applications are now available for word processing, emailing, automated remote file backup, and a host of business and personal services. All of these applications – and many others we haven’t even dreamed of yet – are going to require much greater bandwidth than what is generally available today, even from “broadband” providers. All this adds up to consumer bandwidth demands that are growing at an enormously high rate, and are projected to grow for years to come. Can our current last-mile bandwidth capabilities handle this? Consider the following....

  • In 2015, Internet video will be nearly 700 times the U.S. Internet backbone in 2000. It would take well over half a million years to watch all the online video that will cross the network each month in 2015. Internet video will generate over 18 exabytes per month.
  • Internet video is now approximately one-third of all consumer Internet traffic, not including the amount of video exchanged through P2P file sharing. Currently, Internet video has surpassed P2P in volume. This will be the first time since 2000 that any application has displaced P2P as the top traffic driver.
  • The sum of all forms of video (TV, video on demand, Internet, and P2P) will account for over 91 percent of global consumer traffic by 2015. Internet video alone will account for over 60 percent of all consumer Internet traffic in 2015.
  • Video communications traffic growth is accelerating. Though still a small fraction of overall Internet traffic, video over instant messaging and video calling are experiencing high growth. Video communications traffic will increase ten-fold from 2010 to 2015.
  • Real-time video is growing in importance. Internet TV, video communications, and ambient video are all high-growth application categories. By 2015, Internet TV will be over 4 percent of consumer Internet traffic, and ambient video will be 8 percent of consumer Internet traffic. Live TV has gained substantial ground in the past few years: globally, P2P TV is now slightly over 7 percent of overall P2P traffic at over 200 petabytes per month.
  • Video-on-demand (VoD) traffic will double every two years through 2015. The twin trends of on-demand viewing and high-definition video are generating very rapid growth in cable video and IPTV traffic transported over IP in the metro. Consumer IPTV and CATV traffic will grow at a 53 percent CAGR between 2010 and 2015, compared to a CAGR of 40 percent for consumer Internet traffic.