Page 1 You are here - Index and definitions
2. The Village situation
3. Decisions decisions
Bandwidth - the amount of data required for a particular purpose
Kilobit - a thousand bits of wot a computer works with
Megabit - a million bits of wot a computer works with
Gigabit - so many you need not worry
ISP - Internet Service Provider - you pay them and they 'bring' the broadband to you
Unbundling - where BT allow an ISP to install their equipment in an exchange to handle broadband for their customers. This results in cheaper contracts but no change in delivered speeds.
Contention Ratio - in simple terms a value for the number of people using a particular broadband feed - typically 50:1 for 'normal' commercial ISPs. The higher the ratio the slower your connection - for example it rises as the school-kids get home and switch on.
Fibre-optic - the new generation 'optical' glass-like cable which can carry lots of Megabits, using light rather than wiggly amps like a copper wire
Exchange - generally considered to be some sort of building housing more gubbins
Cabinet - a green box sitting somewhere with lots of gubbins inside - up to 6 known in the village
Local Copper - the BT term for the manky wiring between your house and the exchange or cabinet
FTTC - fibre running to a cabinet
FTTP - fibre running to your premises
ADSL - 'Asynchronous Digital Subscriber Line' - basic broadband, offering a certain speed for download (typically 512kb) and a much lower speed for upload (hence 'A'synchronous).
ADSLMAX - faster - up to 8mb download and a bit faster upload than ADSL
ADSL2+ - up to 20mb down speed and reckoned to be the fastest copper will carry
BT 21 CN - BT's plans for speeds up to 24mb - still wriggling around in the undergrowth, but being replaced by..............
NGA - New Generation Access - BT's plans for 'fast fibre'. Whether this is another flash in the pan or a real plan we will see
BT Infinity - BT's new fibre plans for speeds up to 'loadsa mb' - thought to be the 'commercial' name for NGA
VOIP (Voice over Internet Protocol) - the option to use the internet for telephone and video contacts. Free calls to anyone else using the same system and a cheap rate for connections to other 'normal' numbers. Generally a speed of more than 1mb is required to make it work well. If you use it you have the option of dropping a land-line contract and thus saving money - as long as your broadband is not being delivered on a BT owned line ie on a normal house connection.