[wellylug] [OT] Internet & Citylink

[Richard Hector]

On Mon, Feb 28, 2005 at 07:59:50PM +1300, Jamie Dobbs wrote:
> David Antliff wrote:
> 
> >On Mon, 28 Feb 2005, Cliff Pratt wrote:
> >
> >>The rule of thumb used to be to divide by 10. That was to allow for 
> >>the overhead of stop and start bits. I guess that only applies to 
> >>serial port lines. I also guess that it doesn't apply to ADSL, but 
> >>I'm not sure why. Anyone care to comment?
> >
> >
> >Because on broadband services the overhead is transparent to the user? 
> >The advertised speed is customer payload rate, not connection speed or 
> >symbol rate or anything like that. So a 256kbps link is 256 * 1000 (a 
> >kilobit is 1000 bits, not 1024) which is 256000/8 = 32000 Bps or 
> >31.25KB/sec.
> >
> 1000 bits is NOT a kilobit (or at least wasn't when I went to either 
> University or Polytech, or in the 25 years I've been using computers).
> The numeric base of computers is powers of 2, and you cannot get 1000 
> from a whole power of 2, the closest you can get is 1024 which is the 
> correct definition of kilo in computer terms.

The data comms people have usually stuck to real prefixes rather than
the weird ones computer people use.

Adopting existing terms for the 1024 multiples was a silly thing to do,
IMHO.

Richard