:: it. I don't know the exact figures but I'd guess there must be frequency
:: components up to the 10Mhz range or more, and given how long phone lines
:: are, they'd make rather nice antennas at those frequencies, twisted pair
:: notwithstanding :) I sometimes wonder about the amount of
:: crosstalk between
:: close pairs that all have ADSL active - not so much a problem now that it
:: is still few and far between, but perhaps a problem in the future as it
:: becomes more common.

If I remember right, the frequency spectrum is from 32KHz to just over 1MHz.
The spectrum is split up into several bins (4KHz each) and the equipment's
supposed to be clever enough to drop bins that are in ranges with
interference -- did I get that right, Daniel?

The ADSL technology used by Telecom is designed to withstand environmental
interference, IOW. Does an arc welder really drown out the whole frequency
spectrum used by ADSL?

As an added datapoint, I didn't experience the micro outages until after the
G.DMT upgrade of the exchanges. This is not saying that the service was
perfect before... experienced outages of several days earlier. Unless
someone's e.g. put up an amateur radio station beaming right at my phone
lines, I am a bit sceptical about the line noise theory.

Also, if there really is major interference, strong enough to drown out the
ADSL signal, surely it would be a) measurable; b) reported by many more
users in the same area and c) last for longer than just a few seconds at the
time?

:: I would respectfully suggest that claiming the majority of users use
:: jetstream just to web browse, and therefore its not much of an issue to
:: them is flat wrong. At the moment Jetstream is expensive, and the type of
:: people that are forking out for it are typically either businesses or
:: "power users" who are likely to be using it for VPN, ssh, and other
:: long-life connections just as much or more than web browsing.
::
:: I myself use ssh to remotely admin servers a lot and it can be
:: *extremely*
:: annoying losing connections unexpectedly, I'm forced to either use
:: something like screen so I can log back in again without what I'm doing
:: getting killed, or a dialup connection, which I never have any problems
:: with. This is rediculous. I'm sure theres plenty of other people on this
:: list in the same boat, and to us, micro-outages might as well be
:: MAJOR-outages.

Yes, I quite agree with the above. Jetstream isn't your typical consumer
grade product, aimed at casual Internet use. I use it the way Simon
described, and would like to do so without these constant niggles.

-- Juha

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Received on Thu Mar 1 10:43:00 2001