Re: [Telecom] Emergency call boxes still in use article

I routinely -- as in several times a week -- encounter 'unable to complete

> your call' intercept messages and/or fast busy.

Where is that and why is that? Maybe the cities I've lived and worked in had some magic touch, but I never encountered such poor service "routinely several times a week". Here and there were very occassional spot shortages over the years. but not "routinely".

Trunks, on the other hand, are still relatively "expensive". and always > will be. Before you consider things like '3-way' calling, that can tie > up more trunks than premise lines.

A trunk consists of both the physical conductor between two locations as well as the terminal equipment on each end. The terminal equipment is VASTLY reduced in price. The physical conductor is vastly reduced in price thanks to digital and fibre optics and greater economies of scale. In other words, the CO switch is larger than it once was on a per line basis, and there are more trunking and routing options on a per line basis than years ago.

Likewise the switchgear in the C.O. is vastly cheaper so they can afford more of it as a safety reserve.

Let's look at it another way. Back in 1975 when a major NYC telephone exchange burned up ("Second Ave"), the lines that used ESS were the easiest to quickly restore using other ESS switches elsewhere and swap in replacement. Today everything is ESS. That means in case of a big problem, they can, and they do, reassign resources via computer redirect rather than have guys out with soldering guns and circuit plans.

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I think you are confusing ESS with DACS/DCS. Two different animals.

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Justa Lurker

But there are still physical subscriber lines that terminate in offices. It's not so easy to re-home them if the CO burns to the ground like what happened in NYC.

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Where: big city, central financial district.

Why: I make a _lot_ of calls during busy hours, into similarly congested areas. Almost all of them inter-LATA.

Note: the blockages are momentary, I almost _never_ get a repeat failed call on a redial.

Ignoring the labor cost, you have a point. unfortunately, labor _is_ a big, and *ever-rising* part of the total cost picture.

Reply to
Robert Bonomi

How is it that a computer can restore service to a telephone line that terminated in a burned out exchange? When the insulation burns off of the cables entering the exchange those pairs are history. Nothing but rebuilding the burned up cables will restore service. That outside plant is not a set of computer routing tables it is individual pairs of copper wire that must remain intact, insulated from each other, insulated from all other pairs, and insulated from ground if it is to carry a signal from the subscriber to the PSTN. -- Tom Horne

***** Moderator's Note *****

I think the original poster was referring to the fact that the increased bandwidth available from fiber made it possible to do "fork lift upgrades" of the existing local pairs by reterminating them into SLC boxes, which could be connected to _other_ exchanges by fiber, thus speeding the return of service.

Do any of the readers have direct knowledge of the disaster and the repair effort? The only film I ever saw was just a lot of cables being run, but it seems that swapping the subscribers into SLC would have made the re-routing via other exchanges possible.

Bill Horne Temporary Moderator

-- Please put "[Telecom]" (without the quotes, but _with_ the brackets) in your Subject: line, or I may never see your post. Thank you.

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