optic fibre, page-7

thanks to crikey.com.au

Crikey’s resident nerd and lapsed tech journalist Marcus Westbury writes:



ADSL and ADSL2+ (not ADLS or ALSD!) is the technology used to send relatively fast internet over the existing copper wires from the local exchange to your home or business. It’s a lot faster than the old dial-up technology but it doesn’t work at long distances from an exchange and is not as fast as fibre optics.


WiMAX is the system that the government is subsidising Optus and Elders to roll out across regional Australia. It uses radio waves to send high speed services over large distances. WiMAX is to WiFi (used by many people around homes, offices and cafes) as the mobiles are to cordless phones. On paper it looks like a cheap solution but it has never been rolled out on this scale before, there are tradeoffs between distance and speed, and many users are sharing the available bandwidth. Actual speeds may depend on how popular it becomes.


Fibre to the Node brings high speed fibre optic data connections to street level. The “node” is the little hub on the street where phone lines from individual lines link into the main lines back to the exchange. Fibre to the node allows much higher speeds for data – although not as fast as fibre all the way to your home or office. While it is presented as an argument about broadband, the FTTN debate being played out is really about who controls the next generation of telecommunications infrastructure running down our streets.


A Megabit is a million bits of data or 125k. Megabits are generally used to describe rates of data transfer over networks. Using first generation ADSL technology 1.5 megabits is the common maximum speed, but in built up areas 12 Megabits per second is not uncommon already using ADSL2+ but speeds depend on how close you are to the exchange or the fibre node.


A Megabyte is a million bytes of data or about or 1000k. As a much larger unit, megabytes are generally used to describe memory and storage capacity on computers