Re: Busy out POTS line

"Phil McKerracher" <phil.removethistoreply@xxxxxxxxxxxxxxx> wrote:
>"Floyd L. Davidson" <floyd@xxxxxxxxxx> wrote in message
>news:87vewcu4c8.fld@xxxxxxxxxxxxx
>> "Phil McKerracher" <phil.removethistoreply@xxxxxxxxxxxxxxx> wrote:
>
>> 3) There are *not* thousands of subscribers busying out lines.
>
>No? What makes you think that?

Experience.

>> >> >Phone companies don't like this, so they usually remove the feed after
>a
>> >> >while.
>> >>
>> >> They automatically put it back too, the instant you put the
>> >> phone back on hook.
>> >
>> >Not instantly, because they can't detect if you're on hook if there's no
>> >feed.
>>
>> Instantly... try it and see.
>
>Tried it. No dialtone.

So just how long *did* it take before dialtone was restored?

>Not all networks work like alaskan ones.

It has nothing to do with "Alaskan ones". Alaska is of course
simply one part of the US PSTN, though granted it was way ahead
of the rest of the country when it comes to digital switching,
and therefore no doubt was way ahead in ignoring locked out
lines too.

It depends on the manufacturer of the switching equipment. I've
pointed that out more than once. My line is from a DMS-10
switch (made by Nortel). All of the DMS switches deal with line
lock outs in the same basic way last time I knew...

We might note also that it is a safety issue too, because
someone who needs to dial 911 can do so instantly if the lockout
is released instantly. Not so if it isn't... not good.

>> I'll leave it to you to realize how that can be done "if there's
>> no feed". (Maybe I should hint that "no feed" doesn't
>> necessarily mean no loop current...
>
>I know how it's done, I've designed SLICs.

Then you should know what's wrong with the comments you've been
making...

>In the case I was talking about
>there really is no loop current. There's also a "parked" state with reduced
>line current.

There are several ways to accomplish the same effect. Please do
not insist that everyone's line gets locked out and cannot be
used because there is no loop current, that there will be
thousands of lines in lockout, that the cost of electricity to
provide loop current to those lines is significant, or that
telco's normally initiate maintenance tickets on locked out
lines.

The point is *still* that the way telco's themselves lock out an
inservice telephone line typically is to simply take it offhook
and leave it that way.

>> ... No phone company in the US has
>> been interested in tracking down offhook lines since common
>> control switching systems became ubiquitous.
>
>Interesting. But it's different here.

Frankly I don't believe you.

It doesn't make an ounce of sense to do so, and that's why
nobody on this side of the pond bothers to monitor lines that go
into lock out.

--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>
Ukpeagvik (Barrow, Alaska) floyd@xxxxxxxxxx
.

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