On 09/02/14 23:04, Tim Streater wrote:
In article , The Natural Philosopher
wrote:

On 09/02/14 15:38, Andy Dingley wrote:
On Saturday, 8 February 2014 17:24:37 UTC, David Paste wrote:
Would using coax for the last stretch to the subscriber's premises
provide any better quality of service?

Broadly, no. Twisted pair is surprisingly good as cabling for high
bit rate digital.

Coax developed for analogue signals. It's good at avoiding lots of
problems that affect high bandwidth analogue. When digital telephony
began over the local loop (ISDN, early '80s) it was discovered that
pairs worked surprisingly well and also also that the problems
affecting pairs (dispersion for one) weren't problems that were quite
so important to this type of signal. Closely spaced twisted pair
(with terminations designed to work with it) is even better. As it's
also far cheaper, this is one reason for 10baseT replacing both thick
& thin coax for Ethernet.

Sasy rather that advanced adaptive signal processing and modulation
schemas made ADSL over existing copper possible in a way it wasn't
before.

Not quite the story for Ethernet as that was always possible but the
cost of having a switch held it back a bit, until the cost of all
that coax and the unreliability in large networks made todays
arrangement vastly cheaper...

Unreliable it is if you've ever had to make a tap on thick ethernet -
or had smart-alec physicists think they can just add 50m of their own
2mm thick 50 ohm coax on the end of a segment of thin ethernet.

BTDTGTTS. Try 70 dumb users on one length of coax.


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Ineptocracy

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members of society least likely to sustain themselves or succeed, are
rewarded with goods and services paid for by the confiscated wealth of a
diminishing number of producers.