WHAT IT
ALL MEANS
ADSL
ADSL stands for Asymmetric Digital Subscriber Line – a broadband service
(digital) that’s carried on normal copper phone wires (subscriber lines).
It uses a higher frequency spectrum than voice traffic, which is why it
doesn’t interfere with your phone calls, even though they share the same
line. It’s called ‘asymmetric’ because it’s configured so that downloads will
go faster than uploads, to optimise most people’s web usage.
BANDWIDTH
Bandwidth is just data capacity. Broadband services can carry huge
amounts of data. Low bandwidth or ‘narrowband’ services, like dial-up,
carry far less. Bandwidth is usually expressed in terms of data flow
– 256 kbps or 512 kbps, for example – because it translates into speed
when you’re browsing the internet.
BITS PER SECOND
Most internet service providers, including Telstra, rate broadband plan
speeds in kilobits per second (eg 256/126 kbps). However, most software,
including Internet Explorer and Windows, displays download speeds in
kilobytes per second (kBps). One byte equals eight bits, so typical plan
speeds ‘translate’ as:
PLAN SPEED
KIL OBITS (kbps)
KILOBYTES PER SECOND
(kBps)
1500
187
8000
1000
20000
2500
29 30