David, Big 'state of the copper' article here: http://www.abc.net.au/technology/articles/2013/09/19/3851924.htm
Huge list of copper experiences from Telstra techs, experts and customers here: http://www.abc.net.au/technology/articles/2013/09/18/3851118.htm Richard's referred-to paper on fibre in a mudslide here: http://www.corningcable.com/WorkArea/showcontent.aspx?id=7755 Another lightening strike article here: http://www.fiberopticlink.com/Industry_Solutions/lightning.html The latter two taken from here: http://www.abc.net.au/technology/articles/2013/02/21/3695094.htm Bestest, Nick On 9 January 2014 07:24, David Boxall <[email protected]>wrote: > Thanks Richard. > > On 8/01/2014 10:33 PM, Richard wrote: > > Well, you could stop bothering to try to teach sense to idiots. > > > They're better organised than that. When I counter one line, they just > come back with another. > > They won't learn; learning wouldn't further their cause. My concern is > with the silent reader, who risks being misled. > > > But I have a real, current and close experience. Lightning. A lightning > > strike in Wentworth Falls - one lightning strike - destroyed the > > insulation in a cable run. I spent Monday afternoon with a Telstra tech, > > starting at the termination point at my business and working back to > > find where the damage ended. > > > > The result of this one lightning strike is that a 100-metre cable run > > has been rendered useless. There is one good pair left, which happened > > to belong to my neighbour. I just happened to be the first to complain - > > and the result will be that Telstra has to trench new cable for the > > whole run. > > > You're lucky you weren't on the 'phone at the time. I've already linked > to <http://www.snopes.com/horrors/techno/phone.asp>. That successfully > neutralised the backup battery objection. There used to be a warning in > the paper 'phone book; is that still so? > > > The copper *network* could be maintained forever, but only with regular > > maintenance and replacement. Some of that is that to keep copper in > > pristine conditions, you have to provide it with an ideal environment. > > That means doing things like giving it a pressurised environment (which > > costs money). > > > I've heard repeatedly that the service life of copper cable is 30 to 50 > years, depending on environment. Why is that? What happens to the cable? > My neighbour's report is interesting, but I need a more credible source. > > In my area, line noise and reliability degraded to the point that > Telstra had to replace the cable. So what caused the degradation? If it > was just joint failure, why replace the whole cable? > > > Optical fibre, on the other hand, is nowhere near as fussy. There is a > > Corning study which I've linked to before here, in which a fibre cable > > was retrieved after 20 years of flood-heat cycles, in which the glass > > showed no measurable deterioration from when it was new. > > > If you could repost that link, I'd be grateful. > > > You might also think about this: Australia has zero copper-based > > submarine cables still in service. On the other hand, I am not aware > > that Australia has *ever* decommissioned a submarine fibre. > > > > RC > > > -- > David Boxall | ignorance more frequently > | begets confidence than does > http://david.boxall.id.au | knowledge > | --Charles Darwin (introduction > | to 'The Descent of Man' 1871) > _______________________________________________ > Link mailing list > [email protected] > http://mailman.anu.edu.au/mailman/listinfo/link > _______________________________________________ Link mailing list [email protected] http://mailman.anu.edu.au/mailman/listinfo/link
