On Friday 08 October 2004 8:28 pm, Chris Green wrote:
Well I suppose what we're getting is DSL, it's broadband (512kB/s in our case) and it's symmetrical. It's a radio system, we're on a rural exchange which won't get ADSL for a while yet.
DSL describes a carrier technology (Digital Subscriber Line) not a bandwidth capability. Because DSL is commonly used to provide Broadband internet connections it is often assumed that DSL and Broadband mean the same thing.
For example NTL cable users have broadband, but do not technically have DSL
For those who are interested DSL can come in several flavours, including
ADSL - Asymmetric Digital Subscriber line
This is by far the most common one, Asymmetric because it usually only provides 256Kbps upstream. Main benefit is it works over reasonable distances, modems are cheap and it does not disturb any PSTN telephone equipment (or use of the line to make PSTN calls) as long as microfilters are used correctly.
SDSL/HDSL - Symmetric/HIgh Speed Digital subscriber line.
Two competing technologies that essentially achieve the same thing.
up to 2Mbs in both directions, downside over ADSL is that it totally occupies the line it is routed over (the line can not be used for PSTN calls once this has been enabled) and the modem hardware can be expensive.
VDSL - AFAIK not actually deployed anywhere yet. 1.5-2.5 Mbps upstream and a wopping 52Mps downstream
When you hear people reffering to DSL or xDSL they are generalising the different variants, in the same way that Computer can mean Commodore Pet, IBM Mainframe or X86 PC :o)