Wow!  I knew there was confusion out there about this, but I didnt realize
just how much (even on my part it would seem).  Here’s one possible source
of clarification:

http://www.speedguide.net/Cable_modems/bandwidth.shtml

and another:

http://www.scotsnewsletter.com/best_of/dtrct.htm
(not this Scott's newsletter by the way - I just happened across it doing a
yahoo search on the matter)

The consensus seems to be that there should be made a distinction between a
"binary Kilo" (with a capital “K”) and a "decimal kilo" (with a lower-case
“k”).  This, I think, was already well-established and agreed to but it sure
is easy to get sloppy with that capitalization and terminology.

kbit = 1,000 bits (decimal 10^3)
kByte = 1,000 bytes (decimal 10^3)

Kbit = 1,024 bits (binary 2^10)
KByte = 1,024 bytes (binary 2^10)

As I understand it, most modern hard drives are now rated in decimal format
(I’m pretty sure it used to be binary, but I’ve read in several different
places that the industry migrated to decimal sometime back -- probably as a
marketing gimmick).  That is, 1 kByte (or even KByte in this special case)
of storage actually equals 1,000 Bytes or 8,000 bits instead of 1,024 Bytes
or 8,192 bits.  Memory is apparently still rated in binary Kilo bits/Bytes. 
That is, 1 KB of memory is 1,024 Bytes or 8,192 bits.

All WAN connections always have been and still are rated in decimal format. 
That is, 1 kbps equals 1,000 bits/sec and 1 kB equals 1,000 Bytes (or 8,000
bits)/sec.  I'm not aware of throughput ever having been expressed in binary
Kbits or KBytes (at least not in the "telecom" world).  Maybe computer geeks
did that, but it only served to confuse the matter more if they did.  If a
download test were to return results in true binary KBytes/sec, you would
first have to multiply that number of KBytes by 1,024 and then multiply by 8
to get the true decimal number of bits/sec.  Perhaps tests some do.  Perhaps
some don’t.  Probably it’s a mess of a mix that resulted from all this
confusion.

Software weenies still seem to deal with binary Kilo, regardless of whether
it’s bits or Bytes.  But I’m not one of them, so I can’t make this last
statement definitively.

Sheesh.  

 





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