29 Years of the Digest ... founded August 21, 1981
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The Telecom Digest for July 06, 2011
Volume 30 : Issue 166 : "text" Format
====== 29 years of TELECOM Digest -- Founded August 21, 1981 ====== |
Telecom and VOIP (Voice over Internet Protocol) Digest for the
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we do not want the kind of world that results when no one stands
against crime. - Geoffrey Welsh
See the bottom of this issue for subscription and archive details
and the name of our lawyer, and other stuff of interest.
|
Date: Mon, 04 Jul 2011 09:08:35 -0500
From: GlowingBlueMist <glowingbluemist@invalid.telecom-digest.org>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: "Underground" demarc?
Message-ID: <4e11c96c$0$12943$892e0abb@auth.newsreader.octanews.com>
On 7/1/2011 12:59 PM, grumpy44134 wrote:
> My friend is having an intermittent problem with her home phone. I
> told her to find the gray demarc/Telephone Network Interface (Ohio)
> box. After not being able to find it, she reminded me her power and
> telephone wires were underground to her house. Question - where is
> the demarc for underground telephone service (in Ohio)?
>
I have lived in many states, not Ohio, but in the old homes I lived in
that had phone service hooked up between the 50's and 60's the phone
cable aerial or underground terminated at a phone company junction block
either in the basement or the crawl space.
Most of those older homes did not have a modern phone demarc inside or
outside unless repair work had been done by the phone company in the
last 10 years or so. They just had the black plastic looking block with
the 4 terminal screws. Two for the actual phone line and two screw
terminals for the rest of the house phone wiring. A ground wire is
normally attached to the block as well.
After physically verifying if the more modern phone demarc, with the
RJ-11 jack, is missing you might give her phone company a call. In
homes where I lived in Massachusetts and Iowa they came out and
installed them for free once I requested them. It has been 10 years or
so since I last had one installed so things may have changed.
Just be sure to nail down if the installation would actually be for free
or if they would charge for the installation of the new demarc.
Date: Mon, 4 Jul 2011 06:50:48 -0700 (PDT)
From: Tom Horne <hornetd@gmail.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Battery power support today
Message-ID: <b19be6af-9e2a-4bdf-a63e-f54edfaad978@gh5g2000vbb.googlegroups.com>
On Jul 2, 12:40 pm, Lisa or Jeff <hanco...@bbs.cpcn.com> wrote:
> On Jun 30, 9:53 am, klu...@panix.com (Scott Dorsey) wrote:
>
> > Well, the primary argument is, considering that we have had high
> > power AM broadcast in the US for ninety years now, and a whole lot
> > of people have worked in very strong RF fields, that if there was
> > going to be a substantial health risk it would have been noticed
> > almost a century ago.
>
> I'm not sure if that's accurate.
>
> Gong back 40 years, let alone 90, we lived in a world where a great
> many people smoked and were exposed to industrial and automotive
> pollutants in the air and at the worksite. These all could generate
> illness in their own right and mask long-term ill effects from things
> like high power AM transmitters. Things were even worse going further
> back in time. (IMHO, the above-ground nuclear testing of the 1940s
> and 1950s didn't help us any, but I don't know if anything, such as
> increased leukemia rates, have been documented.)
>
> In addition, going way back it seems they focused more on acute health
> effects rather than long term trends. In my readings of WW II
> radiation safety in the Manhattan Engineer District, they focused on
> noticeable immediate radiation effects.
>
> It should be noted that many personnel would not cooperate with safety
> officers because it interfered with their work, and they allowed
> themselves more exposure than permitted. I sense that scientists back
> then belittled the radiation risk. One woman scientist wrote of
> taking radiation measurements of a early reactor while pregnant, and
> she hid her pregnacy so she could still work. I understand there were
> subsequent long term health studies done of MED workers, but they're
> extremely technical and hard to interpret.
>
> Today, many of those pollutants have been eliminated or sharply
> reduced in the US. There's a lot less heavy industry and automobiles
> have stronger pollution controls.
>
> On the flip side, we live in a power-hungry world today with heavy use
> of air conditioning and electronic devices and of course increased
> population. In addition, electricity is sold and transported long
> distances. All that contributes to heavier use of existing high-
> tension lines and the construction of new lines.
>
> Given all that, I can't help but wonder that a study done say in 1965
> is obsolete and would need to be redone reflecting all the above.
You seem to be leaving out the fact that the outside linemen that
maintain these lines are exposed at very close proximity to them and
have been since the first AC transmission lines were built. If there
was a health effect from exposure to EMF, at power distribution
frequencies, then it would have shown up by now. Add to that the
Union operation of the linemens' health plans in many areas since
just after WWII and you can see that any trend of increased morbidity
or mortality would have become known by now.
--
Tom Horne
Date: Tue, 05 Jul 2011 11:44:26 -0500
From: Dave Garland <dave.garland@wizinfo.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Battery power support today
Message-ID: <iuvf1o$vi1$1@dont-email.me>
On 7/4/2011 8:50 AM, Tom Horne wrote:
> You seem to be leaving out the fact that the outside linemen that
> maintain these lines are exposed at very close proximity to them
> and have been since the first AC transmission lines were built. If
> there was a health effect from exposure to EMF, at power
> distribution frequencies, then it would have shown up by now. Add
> to that the Union operation of the linemens' health plans in many
> areas since just after WWII and you can see that any trend of
> increased morbidity or mortality would have become known by now.
Excerpted from
http://www.cancer.gov/cancertopics/factsheet/Risk/magnetic-fields :
> Is there a link between magnetic field exposure at work and cancer
> in adults?
>
> Several studies conducted in the 1980s and early 1990s reported
> that people who worked in some electrical occupations (such as
> power station operators and phone line workers) had higher than
> expected rates of some types of cancer, particularly leukemia,
> brain tumors, and male breast cancer. Some occupational studies
> showed very small increases in risk for leukemia and brain cancer,
> but these results were based on job titles and not actual
> measurements. More recently conducted studies that have included
> both job titles and individual exposure measurements have no
> consistent finding of an increasing risk of leukemia, brain tumors,
> or female breast cancer with increasing exposure to magnetic fields
> at work.
Which seems to leave male breast cancer (perhaps statistical noise).
Of course, these workers probably were exposed to other potential
carcinogens in the course of their employment, too (e.g. PCBs, and the
preservatives used on telephone poles are fairly nasty).
Dave
Date: Tue, 5 Jul 2011 13:04:20 +0000 (UTC)
From: danny burstein <dannyb@panix.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Battery power support today
Message-ID: <iuv24k$c35$1@reader1.panix.com>
In <b19be6af-9e2a-4bdf-a63e-f54edfaad978@gh5g2000vbb.googlegroups.com> Tom Horne <hornetd@gmail.com> writes:
>You seem to be leaving out the fact that the outside linemen that
>maintain these lines are exposed at very close proximity to them and
>have been since the first AC transmission lines were built. If there
>was a health effect from exposure to EMF, at power distribution
>frequencies, then it would have shown up by now. Add to that the
>Union operation of the linemens' health plans in many areas since
>just after WWII and you can see that any trend of increased morbidity
>or mortality would have become known by now.
Or, for that matter, the various crew members
aboard a diesel-electric train locomotive. They'd
be spending pretty much their entire workdays
pretty close to a big generator...
--
_____________________________________________________
Knowledge may be power, but communications is the key
dannyb@panix.com
[to foil spammers, my address has been double rot-13 encoded]
***** Moderator's Note *****
Ah, but it's a DC generator! No changing fields!
Bill Horne
Moderator
Date: Mon, 04 Jul 2011 13:39:01 -0500
From: bonomi@host122.r-bonomi.com (Robert Bonomi)
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Battery power support today
Message-ID: <wN6dnUvJt_tYlY_TnZ2dnUVZ_h2dnZ2d@posted.nuvoxcommunications>
In article <90bb497a-cfed-4850-957f-8f9306f5d7a6@x12g2000yql.googlegroups.com>,
Lisa or Jeff <hancock4@bbs.cpcn.com> wrote:
>On Jun 30, 9:53 am, klu...@panix.com (Scott Dorsey) wrote:
>
>> Well, the primary argument is, considering that we have had high
>> power AM broadcast in the US for ninety years now, and a whole lot
>> of people have worked in very strong RF fields, that if there was
>> going to be a substantial health risk it would have been noticed
>> almost a century ago.
>
>I'm not sure if that's accurate.
>
>Gong back 40 years, let alone 90, we lived in a world where a great
>many people smoked and were exposed to industrial and automotive
>pollutants in the air and at the worksite. These all could generate
>illness in their own right and mask long-term ill effects from things
>like high power AM transmitters.
FALSE TO FACT.
Epidemiology looks for *differences* in populations, both in observed
medical conditions, and in background 'environment'.
a 'measurable, and statistically significant' difference in two populations,
is effectively _independent_ of anything else to which both populations
are equally exposed.
> Things were even worse going further
>back in time. (IMHO, the above-ground nuclear testing of the 1940s
>and 1950s didn't help us any, but I don't know if anything, such as
>increased leukemia rates, have been documented.)
Long-term research, done on an ongoing basis from the 1950s onward,
indicates a (for all practical purposes) zero difference in the
incidence of =anything=, among those with relatively close/direct
exposure to said above-ground testing. The largest, "most significant"
difference between those so exposed, and the "general population" was a
lower (albeit by a relatively minor amount) rate of certain illnesses.
=THAT= difference was attributed to other differences between the 'close
exposure' population and the general population.
US DoD, on multiple occasions, had large numbers (i.e., division+) of
'unprotected' troops relatively close to above-ground tests. This was
to establish 'how soon', and 'how well', troops were able to function
militarily after being in the immediate vicinity of a blast. My father,
a career Army Reserve officer, was one of those guinea pigs. The Army
did follow-up check-ups for the rest of his life.
>On the flip side, we live in a power-hungry world today with heavy use
>of air conditioning and electronic devices and of course increased
>population. In addition, electricity is sold and transported long
>distances. All that contributes to heavier use of existing high-
>tension lines and the construction of new lines.
The "most dangerous" electric household device, for the last circa 50
years, is a TV set (or computer monitor) using a CRT. Confirmed increased
incidence of cancers, and other illnesses, among those who are closely
in front of them for extended periods, on a continuing basis. Color CRTs
are a known source of X-Ray emissions.
>Given all that, I can't help but wonder that a study done say in 1965
>is obsolete and would need to be redone reflecting all the above.
The 'field-strength' characteristics of AC power distribution, and of
RF transmission are "well understood", and have not changed one iota
over time. *Regardless* of what else is in the environment, the "inverse
square" law still applies. In the 'old days', there were more people
who were exposed to much higher levels of such things for extended
periods than there are today.
Unless one wants to posit:
a) that there is a 'threshold' level of exposure, above which 'damage'
occurs
b) that, below the aforementioned threshold, there is no such 'damage'.
c) that the amount of damage is the _same_, regardless of 'how far' over
that threshold the exposure is,
d) that the effects are cumulative over time, but not cumulative as
to the 'intensity' of the exposure.
there is simply no rational basis for assuming prior research is 'obsolete'
or in any way 'inaccurate'.
The simple fact is that a toaster, electric waffle-iron, electric
refrigerator, window air-conditioner, or _especially_ an electric stove,
generates a stronger field within the room it is in than an electric power
line at 1000' does.
Date: Tue, 05 Jul 2011 22:15:32 +1000
From: David Clayton <dcstarbox-usenet@yahoo.com.au>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Battery power support today
Message-ID: <pan.2011.07.05.12.15.31.627471@yahoo.com.au>
On Mon, 04 Jul 2011 13:39:01 -0500, Robert Bonomi wrote:
.........
> The simple fact is that a toaster, electric waffle-iron, electric
> refrigerator, window air-conditioner, or _especially_ an electric stove,
> generates a stronger field within the room it is in than an electric power
> line at 1000' does.
Not to mention electric blankets - imagine the amount of field strength
virtually surrounding you for an extended period for those who disregard
the warnings and have them powered up whilst they sleep!
--
Regards, David.
David Clayton
Melbourne, Victoria, Australia.
Knowledge is a measure of how many answers you have, intelligence is a
measure of how many questions you have.
***** Moderator's Note *****
I have mine connected to DC, so it's not a problem. ;-)
Bill Horne
Moderator
Date: Mon, 04 Jul 2011 14:18:36 -0500
From: bonomi@host122.r-bonomi.com (Robert Bonomi)
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: "Underground" demarc?
Message-ID: <QMWdnUQMOaiRj4_TnZ2dnUVZ_sCdnZ2d@posted.nuvoxcommunications>
In article <5717f906-9695-4ae9-ac0c-5dfe7dc8add7@em7g2000vbb.googlegroups.com>,
grumpy44134 <grumpy44134@gmail.com> wrote:
>My friend is having an intermittent problem with her home phone. I
>told her to find the gray demarc/Telephone Network Interface (Ohio)
>box. After not being able to find it, she reminded me her power and
>telephone wires were underground to her house. Question - where is
>the demarc for underground telephone service (in Ohio)?
>
Authoritative answer: "it depends".
First off, it is possible that there is no such "device". For existing
single-family dwellings, the ILEC tended to install a NID/demarc device
only when they had occasion to make a 'premises visit' for some other
reason.
Secondly, some 'underground' service to single-family structures runs
underground to the foundation of the building, then goes up the outside
of the foundation wall, to the level of the ground-floor, and then enters
the building. In -that- situation, the NID/demarc is usually installed
on the building exterior at approximately the point where the wiring goes
through the exterior wall.
Otherwise underground service may enter the structure below ground level,
right through the foundation, In this situation, the NID/demarc (if any)
is found inside the building, in the basement, usually in the rafters right
by where the wiring enters.
Secondly, it is 'not necessarily' gray. A demarc for interior installation
may well be 'telco beige' -- about twice the size of a regular surface-mount
jack, with a short (less than 6") cord that plugs into a modular jack, all
part of the same assembly..
IF there is no NID, per se, then, generally, the telco 'legal liability'
is up to the first splice point in the wiring, 'at or inside' the building.
Things can get complicated if the structure is something like a townhouse.
Date: 5 Jul 2011 16:35:50 -0000
From: "John Levine" <johnl@iecc.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: "Underground" demarc?
Message-ID: <20110705163550.6412.qmail@joyce.lan>
>_IF_ there is no NID, per se, then, generally, the telco 'legal liability'
>is up to the first splice point in the wiring, 'at or inside' the building.
>Things can get complicated if the structure is something like a townhouse.
In my (limited) experience, even if there's no official demarc,
there's invariably a lightning protection block, with four or more
screw terminals, cylindrical fuses, and a ground wire.
R's,
John
Date: Tue, 5 Jul 2011 12:21:18 -0700 (PDT)
From: Lisa or Jeff <hancock4@bbs.cpcn.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: "Underground" demarc?
Message-ID: <78a08c2d-f52e-4363-82b2-786d7fe76889@e7g2000vbw.googlegroups.com>
On Jul 4, 3:18 pm, bon...@host122.r-bonomi.com (Robert Bonomi) wrote:
> IF there is no NID, per se, then, generally, the telco 'legal liability'
> is up to the first splice point in the wiring, 'at or inside' the building.
> Things can get complicated if the structure is something like a townhouse.
What is the definition of the "first splice piont in the wiring"? Is
that where the house line branches out of the cable, where the line
splits to serve various extension telephones in the dwelling, or
something else?
What is the policy for older multi-family housing? Ours has a large
junction box that serves many dwelling units. In a sense, this
junction box could be seen as a demarc, but since many people are
served by it, I would think access is restricted to phone co personnel
only (to avoid accidental or intentional disruption to someone else's
service, plus, the terminals could be poorly labeled.)
(In our building, there are multiple jacks for extension phones within
each unit, but no one 'centralized' jack for the unit.)
Also, how would FIOS be installed in a multi-family building? I would
guess the FIOS boxes would be placed adjacent to the old landline
junction box, or would entirely new wiring methods be used? FWIW,
cableTV lines are simply punched right through exterior walls.
Date: Mon, 4 Jul 2011 13:53:04 -0700 (PDT)
From: Lisa or Jeff <hancock4@bbs.cpcn.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: "Underground" demarc?
Message-ID: <8db5209e-81c4-4735-bf3d-63f4123567a9@s17g2000yqs.googlegroups.com>
On Jul 1, 1:59 pm, grumpy44134 <grumpy44...@gmail.com> wrote:
> My friend is having an intermittent problem with her home phone. I
> told her to find the gray demarc/Telephone Network Interface (Ohio)
> box. After not being able to find it, she reminded me her power and
> telephone wires were underground to her house. Question - where is
> the demarc for underground telephone service (in Ohio)?
Check carefully around the outside of the house.
If this is an older property, it is possible there was never a
physical demarc installed (like in my case.)
Date: Mon, 4 Jul 2011 19:20:18 -0700 (PDT)
From: Lisa or Jeff <hancock4@bbs.cpcn.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Battery power support today
Message-ID: <8f9d3cb4-6037-4a45-8755-4949cc8865ba@p6g2000vbj.googlegroups.com>
On Jul 3, 7:48 pm, Sam Spade <s...@coldmail.com> wrote:
> I don't think N.E.T. ever concentrated subscriber lines going through
> SLC-96 in a way that would deny dial tone at any time, but that may
> have been only in Massachusetts: in the 1960's, the company had
> installed electromechanical concentrators to maximize cable usage in
> low-profit areas, but the DPU made N.E.T. remove them because of
> political backlash.
The Bell Labs history 1925-75 talks about concentrators. In brief,
the 1A provided service to 50 or 100 lines over 10 or 20 trunks with
crossbar links. Starting in 1961 4,300 units were built, but no more
than half were in use at any one time. They were primarily used to
defer installing new cable. The LSS was developed in 1977 providing
for 96 lines on 32 trunks using graded multiple concepts. I think
these units allowed subscribers to connect at the concentrator level
instead of tying up two trunks all the way to the central office; that
is, if two neighbors wanted to talk to each other, the concentrator
(along with CO logic control), handled the call.
One anonymous critic of the Bell System wrote that being served by a
concentrated line was a service disaster. Whether that was true I
don't know. But the Bell System did get hit with a service crisis in
various parts of the country in the 1970s, partly because service
demands outpaced capacity. (There were other factors, too). That is,
new communities were built faster than adequate trunks and switching
could be placed to serve them, and people used their telephones more.
Some more affluent families obtained second lines for their kids. A
physical plant engineered and built for 1950s usage won't do well in
the 1970s.
Today of course swicthgear is far, far cheaper in price so there is
more capacity.
Date: Tue, 5 Jul 2011 08:11:37 -0400
From: Monty Solomon <monty@roscom.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: The enemy of my enemy
Message-ID: <p06240809ca38ae8b817a@[10.0.1.6]>
The enemy of my enemy
July 1, 2011
Nortel Networks, the bankrupt Canadian telecom company, came that
much closer to disappearing completely yesterday with the cash sale
of its portfolio of 6000 patents for $4.5 billion to a consortium of
companies including Apple, EMC, Ericsson, Microsoft, Research In
Motion (RIM), and Sony. The bidding, which began with a $900 million
offer from Google, went far higher than most observers expected and
only ended, I'm guessing, when Google realized that Apple and its
partners had deeper pockets and would have paid anything to win. This
transaction is a huge blow to Google's Android platform, which was
precisely the consortium's goal.
...
http://www.cringely.com/2011/07/the-enemy-of-my-enemy/
Date: Tue, 5 Jul 2011 08:11:37 -0400
From: Monty Solomon <monty@roscom.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Dealtalk: Google bid "pi" for Nortel patents and lost
Message-ID: <p0624080aca38afa5c397@[10.0.1.6]>
Dealtalk: Google bid "pi" for Nortel patents and lost
Nadia Damouni
July 1, 2011
NEW YORK (Reuters) - At the auction for Nortel Networks' wireless
patents this week, Google's bids were mystifying, such as
$1,902,160,540 and $2,614,972,128.
Math whizzes might recognize these numbers as Brun's constant and
Meissel-Mertens constant, but it puzzled many of the people involved
in the auction, according to three people with direct knowledge of
the situation on Friday.
...
http://www.reuters.com/article/2011/07/02/us-dealtalk-nortel-google-idUSTRE76104L20110702
Date: Tue, 5 Jul 2011 13:55:38 -0700 (PDT)
From: Lisa or Jeff <hancock4@bbs.cpcn.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Amateur radio as backup communication
Message-ID: <7f485bca-d7de-4001-a458-3bf43195d2c7@p31g2000vbs.googlegroups.com>
Many participants in this newsgroup are interested in ham radio. An
article in the Phila Inqr talks about current activities, including
providing vital communications when other networks are down.
http://www.philly.com/philly/columnists/monica_yant_kinney/20110703_Monica_Yant_Kinney__Amateur_radio_operators_enjoy_nondependence_day.html
***** Moderator's Note *****
QRZ W1AC?
Bill Horne
Moderator
Date: 5 Jul 2011 10:56:35 -0400
From: kludge@panix.com (Scott Dorsey)
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Battery power support today
Message-ID: <iuv8n3$63o$1@panix2.panix.com>
David Clayton <dcstarbox-usenet@yahoo.com.au> wrote:
>
>The biggest concern is that microwave ovens are designed to use a
>frequency that is most efficient for heating water molecules, and devices
>that share that spectrum will also have the same effect.
>
>Guess what sort of molecule the human body mostly is composed of?
Not really. Microwave ovens got put in the 2.4 Ghz band mostly because it
was a range nobody was using for communication and which was convenient for
use as a dumping ground for RF trash. It was not selected for efficiency
of heating.
In fact, a higher frequency would be more efficient. The classical reference
on ths subject is http://prola.aps.org/abstract/PR/v71/i7/p425_1
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Date: 5 Jul 2011 11:24:58 -0400
From: kludge@panix.com (Scott Dorsey)
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: "Underground" demarc?
Message-ID: <iuvaca$6jb$1@panix2.panix.com>
Wes Leatherock <wleathus@yahoo.com> wrote:
>--- On Fri, 7/1/11, grumpy44134 <grumpy44134@gmail.com> wrote:
>
>> My friend is having an intermittent problem with her home phone. I
>> told her to find the gray demarc/Telephone Network Interface (Ohio)
>> box. After not being able to find it, she reminded me her power and
>> telephone wires were underground to her house. Question - where is
>> the demarc for underground telephone service (in Ohio)?
>
>I couldn't tell you about Ohio, but the buried drop serving me in
>Oklahoma rises out of the ground and comes up to the conduit holding
>the electric meter (to which it is grounded) and the demarc is at
>about eye level, accessible to the customer, as it's supposed to be.
If she is in older construction, she may have one of the original
resistive-fuse terminal block demarcs. If so, she can identify it
because it's the thing that connects to the cable rising out of the
ground, the wire coming from the house, and the ground wire. Could be
a silver box or a black plastic tube or various other configurations.
A call to the telephone company will get it replaced with a modern
demarc for free if she wants. This is usually a good idea since it
makes diagnosis of problems easier.
An awful lot of intermittent telephone problems these days seem to be
caused by cheap flaky telephones, and when people have five or six
phones in the house, finding the one that is causing the problem may not
be all that easy.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Date: Tue, 05 Jul 2011 17:08:53 -0400
From: Fred Goldstein <fgoldstein.SeeSigSpambait@wn2.wn.net>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Battery power support today
Message-ID: <20110705210858.AA4795522@mailout.easydns.com>
On Sun, 03 Jul 2011 16:48:41 -0700, Sam Spade <sam@coldmail.com> wrote,
...
>David Scheidt wrote:
> > Sam Spade <sam@coldmail.com> wrote:
> > :David Lesher wrote:
> > :> Sam Spade <sam@coldmail.com> writes:
> > :>
> > :>
> > :>>The exception was a pair-gain provision such as the Bell
> Systems SLC 96,
> > :>>which was used in rural areas and in areas of rapid residential
> > :>>construction. I believe the terminating SLC 96 box had to have local
> > :>>power. Anyone know differently?
> > :>
> > :>
> > :> Oh yes, SLC's need power.
> > :>
> > :>
> > :>>I imagine SLC 96s are long gone for residential suburban areas
> > :>>but they likely still exist in some rural areas.
> > :>
> > :>
> > :> I was just in Aptos/Watsonville CA region, and there are
> > :> SLC-96's on every other corner. The giveway is the line of
> > :> shiny T1 repeater cans feeding same.
Subscriber line carrier is the norm nowadays. Not odd, but the norm,
except near in to the central office (mainly urban areas). SLC-96,
on the other hand, is an old product, from the 1980s, so I would be
surprised if too many of them are still around. The neighborhood I
used to live in in Newton, Massachusetts was served by 14 SLC-96s in
a manhole. I don't know if those are still in place or if a newer
model is there now.
> >
> > :Both of those areas are a mix of suburban and remote rural areas. I can
> > :understand the SLC 96 on a road back in the hills of Aptos where the
> > :there are long distances with no houses, then a cluster of house. But,
> > :if pair gain is being used in the suburban part of Aptos I would think
> > :AT&T would be getting heat from the CPUC.
Pair gain has many meanings. SLCs provided digital pair gain and
high quality transmission. What stank were the analog pair gain
units, like "AML", that superimposed a second line on an analog
line. Newer Digital Line Carriers are all over.
> >
> > Why? Modern nodes support all the services that are expected, like
> > DSL, television, etc. They're fed with high speed backhaul (often
> > fiber in dense areas).
>
>One word: concentration. It's been a long time, but my recollection is
>that the concentration ratio is 6:1. So, no more than 16 subscribers
>out of the 96 that are likely connected in a suburban area will get dial
>tone at any given time. For suburban areas SLC 96s were only suppose to
>be used until the LEC could provide dedicated subscriber loop.
SLC-96 was not a concentrating unit at all. It was the basis of the
TR-08 specification for remote line terminals. A SLC-96 took five
DS1 spans and supported 96 lines. Each T1 has 24 channels; the fifth
span was the spare, in case one of the others failed.
By the 1990s, they had standardized a newer concentraing standard,
GR-303. This takes two to 20 DS1 circuits, takes two signaling and
timing channels from each of the first two, and uses the remaining
44-478 DS0 channels to support up to a couple of thousand lines,
depending on how much concentration you're willing to accept. Since
traffic is generally predictable, line concentration in the field is
not service-impacting unless it's done wrong.
>***** Moderator's Note *****
>
>IIRC, SLC-96's in "Mode 2", at least the way N.E.T. used them, were
>able to provide 100% dialtone (within the limits of the associated CO,
>of course), because they used "half rate" sampling to allow 48
>channels per T-1 span. SLC-96 units had special common boards, and if
>they were inserted into "Mode 3" SLC-96 carriers by mistake, a 1000 Hz
>test tone would be received at 2000 Hz.
There may have been a low-bit-rate option for the SLC-96, but I'm
pretty sure it wasn't the norm. The main issue in deploying DLC is
between "integrated" vs. "universal" mode. An integrated DLC takes
its DS1 spans directly from the switch, digitally. This provides the
highest quality and supports high-speed modems (V.90 52
kbps). Universal DLC has a channel bank in the CO and takes analog
lines off of the switch and digitizes them in the CO, degrading the
signal a smidge via the extra transcoding. New England Telephone
tended to like universal mode because that analog jumper in the CO
was the boundary between the inside plant and outside plant areas of
responsibility, and that bureaucratic distinction was worth more to
the than saving a bundle on wasted CO terminals and having the
network be more reliable and higher quality.
The one advantage of universal DLC is that it can be unbundled
easily. So a CLEC can pick a channel off of UDLC have it delivered
from the CO Point of Termination to the subscriber. IDLC is nailed
to the ILEC's switch. So a given remote location might have mostly
IDLC, but have a single DS1's worth of UDLC to handle buth special
services and unbundled loops.
>I don't think N.E.T. ever concentrated subscriber lines going through
>SLC-96 in a way that would deny dial tone at any time, but that may
>have been only in Massachusetts: in the 1960's, the company had
>installed electromechanical concentrators to maximize cable usage in
>low-profit areas, but the DPU made N.E.T. remove them because of
>political backlash.
Electromechanical concentrators would not work very well. GR-303, on
the other hand, is transparent and works well. SLC-2000 and
Lightspan supported it, as well as pretty much all later
systems. CLECs have used it a lot too, in products like the Lucent
AnyMedia (NGDLC: DSLAM combined with GR-303 DLC), Adtran TA-4303
(GR-303 to TR-08 converter/DACS box) and Zhone MALC.
By the early 1990s, industry standard practice was to use "Serving
Area Concept", in which the copper loop never exceeds 12 kilofeet,
for all new builds. The feeder is fiber optic to a DLC, and copper
is only used for the distribution subloop. In the 2003 Verizon-MA
unbundled network element rate case, they decided that for financial
modeling purposes (describing "forward-looking" current practice, not
what's embedded in the field), in the urban core, all buildings would
be fiber-fed, no copper to the CO at all. This presumes large
buildings with a DLC in them, not single-family homes, which would
still have copper subloops.
--
Fred Goldstein k1io fgoldstein "at" ionary.com
ionary Consulting http://www.ionary.com/
+1 617 795 2701
Date: Mon, 4 Jul 2011 06:28:55 -0700 (PDT)
From: Tom Horne <hornetd@gmail.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Staples resold devices holding consumer data
Message-ID: <603df932-5e27-4e01-a4d0-17e12fa97c67@b21g2000yqc.googlegroups.com>
On Jul 2, 4:52 pm, Monty Solomon <mo...@roscom.com> wrote:
> Staples resold devices holding consumer data
> Canada audit rips Mass.-based chain
>
> By Jenn Abelson
> Globe Staff / June 22, 2011
>
> Staples Inc. has repeatedly put consumers' data at risk in Canada by
> failing to wipe clean returned storage devices that contain sensitive
> information and are then resold.
>
> Those findings were reported yesterday following an audit by the
> Office of the Privacy Commissioner of Canada. The audit included
> tests of storage devices, including computers, USB hard drives, and
> memory cards that had undergone a "wipe and restore'' process and
> were destined for resale.
>
> Of the 149 devices tested, 54 contained customer data, including
> "highly sensitive personal information'' such as health card and
> passport numbers, academic transcripts, banking information, and tax
> records.
>
> "Our findings are particularly disappointing given we had already
> investigated two complaints against Staples involving returned data
> storage devices and the company had committed to taking corrective
> action,'' Canada's privacy commissioner, Jennifer Stoddart, said in a
> statement. "While Staples did improve procedures and control
> mechanisms after our investigations, the audit showed those
> procedures and controls were not consistently applied, nor were they
> always effective - leaving customers' personal information at serious
> risk.''
>
> ...
>
> http://www.boston.com/business/articles/2011/06/22/staples_resold_devices_holding_consumer_data/
I know that this is not a popular approach but what about the users
who returned the storage devices to Staples. Why do we expect to be
taken care of when we are doing stupid stuff.
--
Tom Horne
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