30 Years of the Digest ... founded August 21, 1981
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The Telecom Digest for September 22, 2011
Volume 30 : Issue 238 : "text" Format
====== 30 years of TELECOM Digest -- Founded August 21, 1981 ======
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Telecom and VOIP (Voice over Internet Protocol) Digest for the
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We must fight spam for the same reason we fight crime: not because we
are naive enough to believe that we will ever stamp it out, but because
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.
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Date: Wed, 21 Sep 2011 10:27:51 -0400
From: "T. Keating" <tkusenet@ktcnslt.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Strange new at&t rumors
Message-ID: <8fsj771q9auic47pifhshuatg92hmqc4gr@4ax.com>
On Mon, 19 Sep 2011 16:59:14 -0400, tlvp <mPiOsUcB.EtLlLvEp@att.net>
wrote:
>In
>
>
http://www.zdnet.com/blog/btl/at-t-moves-on-to-last-ditch-efforts-to-save-t-mobile-deal/58351?tag=nl.e550
>
>today: "AT&T is reportedly trying to sell off subscribers and spectrum
>to smaller regional carriers to save its proposed bid for T-Mobile."
>
>Editorializing, ZDnet suggests, "It looks like the idea is that AT&T wants
>to appear like it has less coverage and lacks the resources to expand to
>justify the need for acquiring T-Mobile and its nationwide network - the
>fourth largest in the country - which is what AT&T has been arguing all
>along."
>
>I'm just left scratching my head ... and wondering what my future as
>an erstwhile T-Mobile customer is going to become.
>
Hopefully the District Court won't fall for this trick.
I just ordered (via Walmart ship to store) a Prepaid (no contract)
T-mobile 4G hotspot to replace my deteriorating DSL service.
At the same time my pitiful 27$/mo AT&T POTS service will also be
on the chopping block for cheaper cell phone service.
Date: Wed, 21 Sep 2011 17:59:34 -0400
From: tlvp <mPiOsUcB.EtLlLvEp@att.net>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Strange new at&t rumors
Message-ID: <14q945zml2aa5$.1dtfvd6jatjj9$.dlg@40tude.net>
On Wed, 21 Sep 2011 10:27:51 -0400, T. Keating wrote:
> ...
> I just ordered (via Walmart ship to store) a Prepaid (no contract)
> T-mobile 4G hotspot to replace my deteriorating DSL service.
Interesting -- care to divulge (i) its cost and (ii) the cost of the
data service? I could well be an interested fellow-buyer. TIA!
Cheers, -- tlvp
--
Avant de repondre, jeter la poubelle, SVP.
Date: Wed, 21 Sep 2011 10:59:31 -0500
From: "Gray, Charles" <charles.gray@okstate.edu>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: History - Dial Telephones in the US Senate [telecomm]
Message-ID: <EB96AD4AE15A14498C8EB2B1727528062EBA361BE8@STWEXE3.ad.okstate.edu>
Here is an interesting historical note on our prestigious senators and
advancing technology.
June 25, 1930
Senate Considers Banning Dial Phones
Carter Glass (D-VA)
In the spring of 1930, the Senate considered the following resolution:
Whereas dial telephones are more difficult to operate than
are manual telephones; and Whereas Senators are required, since
the installation of dial phones in the Capitol, to perform the
duties of telephone operators in order to enjoy the benefits of
telephone service; and Whereas dial telephones have failed to
expedite telephone service; Therefore be it resolved that the
Sergeant at Arms of the Senate is authorized and directed to
order the Chesapeake and Potomac Telephone Co. to replace with
manual phones within 30 days after the adoption of this
resolution, all dial telephones in the Senate wing of the United
States Capitol and in the Senate office building.
Sponsored by Virginia's Carter Glass, the resolution passed without objection
when first considered on May 22, 1930. Arizona's Henry Ashurst praised its
sponsor for his restrained language. The Congressional Record would not be
mailable, he said, "if it contained in print what Senators think of the dial
telephone system." When Washington Senator Clarence Dill asked why the
resolution did not also ban the dial system from the District of Columbia,
Glass said he hoped the phone company would take the hint.
One day before the scheduled removal of all dial phones, Maryland Senator
Millard Tydings offered a resolution to give senators a choice. It appeared
that some of the younger senators actually preferred the dial phones. This
angered the anti-dial senators, who immediately blocked the measure's
consideration.
Finally, technology offered a solution. Although the telephone company had
pressed for the installation of an all-dial system, it acknowledged that it
could provide the Senate with phones that worked both ways. But Senator Dill
was not ready to give up. In his experience, the dial phone "could not be more
awkward than it is. One has to use both hands to dial; he must be in a
position where there is good light, day or night, in order to see the number;
and if he happens to turn the dial not quite far enough, then he gets a wrong
connection."
Senator Glass, the original sponsor, had the last word before the Senate
agreed to the compromise plan. "Mr. President, so long as I am not pestered
with the dial and may have the manual telephone, while those who want to be
pestered with [the dial] may have it, all right."
http://www.senate.gov/artandhistory/history/minute/Senate_Considers_Banning_Dial_Phones.htm
Regards.
Charles G. Gray
Senior Lecturer - Information Technology
Oklahoma State University
(918) 594-8433
Date: Wed, 21 Sep 2011 07:26:29 -0700 (PDT)
From: HAncock4 <withheld@invalid.telecom-digest.org>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: ANCIENT telephone transmission
Message-ID: <bb3d88d5-28a2-4652-881a-18511b57cfba@f41g2000yqh.googlegroups.com>
On Sep 16, 8:18~pm, mattrix <mattr...@gmail.VALID-IF-THIS-IS-
ELIDED.com> wrote:
> Turns out that the problem was phase distortion, more than attenuation.
> (I need to study transmission lines :)
This 1922 article explains a long distance cable--the physical
construction, loading coils, and repeaters.
http://www.alcatel-lucent.com/bstj/vol01-1922/articles/bstj1-1-60.pdf
This 1923 article futher discusses transmission.
http://www.alcatel-lucent.com/bstj/vol02-1923/articles/bstj2-1-67.pdf
As to signalling, different ringdown frequencies were used at
different times and locations because of the need to pass through
repeaters and loading coils, to not interfere with telegraph signals
superimposed on the wire, and within the limits of electronics of the
era. The Ball Labs history Vol 1 goes into considerable detail on
this.
Bell System Technical Journal, 1922-1983 index page:
http://www.alcatel-lucent.com/bstj/#1922
Date: Wed, 21 Sep 2011 09:35:03 -0400
From: "Pawlowski, Adam" <ajp26@buffalo.edu>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: EXchanges (was: area code named beer)
Message-ID: <64F0EDB01F6CC04DA6FF870991FC23592AFC7DCE15@MBCCR4.itorg.ad.buffalo.edu>
Date: Tue, 20 Sep 2011 00:50:36 -0400
From: tlvp <mPiOsUcB.EtLlLvEp@att.net>
To: redacted@invalid.telecom-digest.org.
Subject: Re: EXchanges (was: area code named beer)
Message-ID: <mi89yjrouoys$.16iyqtm3qt1o4$.dlg@40tude.net>
On Sat, 17 Sep 2011 20:28:10 -0400, after tlvp wrote
> ...
> Hook-flash dialing was quite a trick to master, if you hadn't quite
> ever needed to before. ...
>
It has come in handy a few times where you need to dial and the "dial"
function of whatever is handy doesn't work.
3) Q.: Will hook-flash dialing still work on today's DTMF-based PBXes?
It does not work with any VoIP "gateway" product I've come across, I can tell
you this. We don't presently deploy these devices anywhere, but, in my own
limited testing, "pulse" dialing doesn't work. If anything, it causes the port
to reset as though you have hung up the phone. If there is an "adapter" made
for such a legacy device, readily available, I don't know.
This had at least stopped my from a novelty project of putting a rotary 1A2
set on our VoIP system here, but, if it were deployed as a "Solution" to
replacing phones in a business type environs, I can see calls coming in from
people who flipped the T/P switch and now cannot dial. I haven't tried on
some of the older equipment like the Merlin Legend , which I should .
Date: Wed, 21 Sep 2011 08:52:34 -0700 (PDT)
From: Mark Smith <marklsmith@yahoo.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: OnStar Begins Spying On Customers' GPS Location For Profit
Message-ID: <1316620354.81741.YahooMailNeo@web65707.mail.ac4.yahoo.com>
On Tue, 20 Sep 2011 22:58:56 -0400 Monty Solomon <monty@roscom.com> wrote:
> OnStar Begins Spying On Customers' GPS Location For Profit
> Posted on September 20, 2011 by Jonathan Zdziarski
> I canceled the OnStar subscription on my new GMC vehicle today after
> receiving an email from the company about their new terms and
> conditions....
Please give information on how to cancel. They even established a new
credit card to charge after my old one was cancelled.
Thanks,
Mark Smith
Date: 21 Sep 2011 02:17:50 -0400
From: "John R. Levine" <johnl@iecc.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Smartphone suggestions?
Message-ID: <alpine.BSF.2.00.1109210216200.38600@joyce.lan>
Any suggestion for my friend who wants a better smartphone? He lives in
NYC but he travels a lot.
I haven't looked at VZW's stuff recently. Do they have anything decent
that will work on foreign GSM networks?
---------- Forwarded message ----------
Date: Sun, 18 Sep 2011 19:53:23 -0700
But here are my desired specs:
- ability to talk and access email simultaneously
- best network coverage domestically
- ability to work overseas
New Verizon Bold or Torch? New ATT Torch? Something else?
Date: Wed, 21 Sep 2011 11:38:39 -0700 (PDT)
From: Mark Smith <marklsmith@yahoo.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Smartphone suggestions?
Message-ID: <1316630319.46295.YahooMailNeo@web65709.mail.ac4.yahoo.com>
On Date: Sun, 18 Sep 2011 19:53:23 -0700 John R. Levine <johnl@iecc.com> said:
> Any suggestion for my friend who wants a better smartphone?~ He
> lives in NYC but he travels a lot. I haven't looked at VZW's stuff
> recently. Do they have anything decent that will work on foreign GSM
> networks?
If overseas use is mandatory get one of the phones that will do that:
the one we were issued at work on Verizon wasn't a smart phone.
But to answer your want list:
> But here are my desired specs:
> - ability to talk and access email simultaneously -
AT&T and I think Sprint feature this in their ads.
> - best network coverage domestically -
Verizon unless you are in the boonies out west.
> - ability to work overseas -
Either get a phone that works overseas, get a GSM phone and switch to
an overseas service by switching chips or if you are overseas enough
buy a pay as you go phone overseas.
Mark
Date: Wed, 21 Sep 2011 13:12:50 -0400
From: "David Chessler" <chessler@remove-this.usa.net>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: House Republicans put pressure on Obama to drop AT&T lawsuit
Message-ID: <895PiuRLY6864S01.1316625170@web01.cms.usa.net>
House Republicans put pressure on Obama to drop AT&T lawsuit
By Brendan Sasso - 09/20/11 03:45 PM ET
One hundred House Republicans wrote to President Obama on Tuesday
asking his administration to settle its lawsuit blocking the merger of AT&T
and T-Mobile.
The lawmakers said the lawsuit "will thwart job creation and economic
growth." [SNIP]
http://thehill.com/blogs/hillicon-valley/technology/182701-republicans-urge-obama-to-settle-atat-lawsuit
***** Moderator's Note *****
The cited page also contains this comment:
"Today's House Republican letter is yet another indication that AT&T's
congressional support for its takeover of T-Mobile comes at a price,"
said Gigi Sohn, president of Public Knowledge. "In this case, the
total is close to $1,000,000. That's how much the company gave to
members of Congress who signed the letter and who are willing to allow
their constituents to be subjected to a wireless market controlled by
only two huge companies."
Bill Horne
Moderator
Date: Wed, 21 Sep 2011 15:18:19 -0400
From: Monty Solomon <monty@roscom.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Data breaches affect 2m in Mass.
Message-ID: <p062408bdca9fe80d1da8@[10.0.1.8]>
Data breaches affect 2m in Mass.
Firms increasingly targets for hackers, Coakley warns
By Hiawatha Bray
Globe Staff / September 21, 2011
Personal information from nearly one out of three Massachusetts
residents, from names and addresses to medical histories, has been
compromised through data theft or loss since the beginning of 2010,
according to statistics released yesterday by the office of Attorney
General Martha Coakley.
A state law enacted in 2007 requires all companies doing business in
Massachusetts to inform consumers and state regulators about security
breaches that might result in identity theft. That could include
leaks of individual names along with other sensitive information,
such as Social Security numbers or bank account, credit card, and
debit card numbers. The law was passed in 2007, after hackers stole
45 million credit card numbers from Framingham-based retailer TJX Cos.
Coakley said that her office is just beginning to analyze the reports
to find out whether the law is helping to reduce data breaches. But
she predicted the problem will get worse as more Americans store
vital personal data on various computer networks. "There is going to
be more room for employee error, for intentional hacking,'' Coakley
said. "This is going to be an increasing target.''
The attorney general's office has received 1,166 data breach notices
since January 2010, including 480 between January and August of 2011.
About 2.1 million residents were affected by the various incidents,
though it's unknown whether any of them were actually defrauded as a
result of the data leaks.
...
http://www.boston.com/business/technology/articles/2011/09/21/two_million_mass_residents_hit_by_data_breach_leaks/
***** Moderator's Note *****
I've said it before, and I'll say it again: it is not security that
enables online commerce, but ignorance. Bruce Schnier has argued that
the $300 limit on credit-card losses is the enabling factor in the
e-commerce boom, but I've come to a different conclusion, and I
contend that it is the fact that those at risk are not even aware of
the chances they are taking. To put no fine point in it, the public
doesn't realize that the electronic banking world is an "overlay" on a
banking security system which hasn't changed since banking was
invented: a system which is based on face-to-face transactions and on
locally-maintained paper records. It is a system that has broken down
in the face of online account access based on nothing more stringent
that password authentication.
Not only is the first line of defense compromised, but the chances of
getting caught while conducting online fraud are vanishingly small:
the only time I contacted the Electronic Crimes Task Force concerning
a fraud attempt which had not succeeded, the Secret Service agent told
me point-blank that they don't have the manpower to pursue any case
with losses under $20,000.00. This isn't some pimple-faced geek in a
basement anymore: organized criminal gangs are conducting every kind
of attack they can while hiding behind foreign flags, using experts
who are receiving part of the profit and international data
connectivity that has, for practical purposes, no means of tracing a
connection or verifying a face.
Although I think Schnier is off the mark on the enabling factor, he is
spot-on about the change-agent that will drive better security: the
insurance industry will, at some point, get tired of paying out
claims, and it will demand a new and (hopefully) more resilient system
that reduces online fraud to manageable levels.
Bill Horne
Moderator
Date: Wed, 21 Sep 2011 15:33:52 -0700 (PDT)
From: "Mark J. Cuccia" <markjcuccia.remove-this@and-this-too.yahoo.com>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: Kansas City MO/KS, Washington DC Metro (was re: EXchanges)
Message-ID: <1316644432.3379.YahooMailClassic@web31106.mail.mud.yahoo.com>
Neal McLain wrote:
> Wes Leatherock wrote:
>> A prime example was the greater Kansas City Metropolitan exchange,
>> since the metro area extended across two states with seven-digit
>> dialing. The Missouri side had area code 816, the Kansas side 913.
[NOTE that I have corrected an error, in the above quoted paragraph]
>> Of course, this consideration ceased to be a factor when
>> mandatory 10-digit (or 11-digit) dialing on local calls came
>> into existence.
> Don't those two cities have independent 7-digit dialing plans now?
> I thought 816 and 913 each had 7-digit dialing internally but
> 11-digit dialing across the river?
Yes, in the Kansas City MO/KS metro area, local/EAS calls within
one's own state/NPA are still dialable as just seven-digits,
although ten-digits (and 1+ten-digits) are permissive for such
intra-state/NPA local/EAS calls,
but local/EAS calls that cross the state/NPA boundary are now
mandatory ten-digits (permissively 1+ten-digits).
The 816/MO side is eventually going to be overlaid with 975. This was
announced by SW-Bell and NeuStar-NANPA ten years ago, back in 2001,
but it has been "on hold" ever since. Whenever that 816/975 overlay
does take effect, then ten-digits mandatory will also take effect for
local/EAS calls within the 816/MO-side. I don't know if at&t/SW-Bell
and the rest of the telco industry, along with Kansas regulatory and
NANPA, will work to make local/EAS calls within the 913/KS-side also
as mandatory ten-digits for "consistency" purposes, nor not. Of
course, whenever the 913/KS-side ever does need relief which is also
most likely going to be an overlay, then ten-digits will become
mandatory for intra-913/KS local/EAS calls as well, if not already so
by then. BTW, 552 is the likely relief code for 913/KS.
**** MAYBE NOT 552! 552 is now a future 5xx PCS code! Also, 913/KS
is NOT expected to exhaust for QUITE some time now (as of 2011) ****
When the Ottawa-ON / Hull-QC metro area needed to eliminate protected
c.o.codes/7-digit local/EAS dialling to delay area code relief by
"squeezing" as much remaining life as possible from 613/ON and 819/QC,
Bell Canada, the CRTC, the CNA, etc. actually made local/EAS dialling
as mandatory ten-digits _throughout the entire_ 613/ON-side and
819/QC-side, even for intra-province/NPA local/EAS calls _everywhere_
in those NPAs, even in places outside of the Ottawa-ON / Hull-QC metro
area. Subsequently, the (entire) 613/ON-side has been overlaid with
343 (in 2010). The (entire) 819/QC-side will be overlaid with 873
next year (in 2012).
> Another example: DC/Maryland/Virginia metro area. Before 1953, the
> entire area had a single 6-digit dialing plan (2L+4D). In '53,
> 7-digit dialing was introduced (2L+5D).
Note that the numbering/dialing of Washington DC Metro (including the
VA and MD suburbs) converting from 2L-4N to 2L-5N was a "staged"
process. There were two or three staggered cutovers affecting specific
exchanges/central offices in various neighberhoods of the metro area
in the late 1940s/early 1950s-era. Other cities which changed from
2L-4N to 2L-5N did it as a single city/metro-wide cutover, where
_everything_ in the entire metro area that was 2L-4N changed to 2L-5N
all at one time, overnight (literally). But not the Washington DC
metro area, nor various other (multi-switch) cities. However, any/all
cutovers in the old electromechanical (SXS, Panel, Crossbar, etc) era
that involved numbering/dialing did NOT have a permissive period, but
such numbering/dialing cutovers were "flash-cut" (or nearly so, i.e.
there might have been an inadvertent permissive dial period for a few
hours or even a few days, as telco had to individually "turn-on" the
new numbering/dialing, and then "turn-off" the old/obsolete numbering/
dialing).
> Sometime later, the dialing plan was split by area code, with
> 10-digit dialing across boundaries.
It was in October 1990, when the correct destination area code was
now required for ten-digit (permissively 1+ten-digit) local/EAS
dialing which crossed the state/district/NPA boundaries between
DC/VA/MD. Permissive ten-digit local/EAS dialing (also permissive as
1+ten-digits) had been in place by BA/C&P for some time prior to
October 1990, though.
> Since then, both Maryland and Virginia have gotten overlays, so the
> metro area now has five area codes with 10-digit dialing in Maryland
> (301 and 240) and Virginia (703 and 571). DC (202 still has 7-digit
> dialing.
[NOTE that I have slightly edited, and corrected an error, in the
above quoted paragraph]
BTW, probably sometime next year, the eastern Maryland (Baltimore,
Annapolis, etc. area), with 410-overlaid-with-443 (since 1997; also
the 301/410 split was in 1991), will get an additional overlay with
667. NeuStar-NANPA/etc. announced this additional overlay in 2001,
but it has never been actually implemented. Also in 2001, the
additional 227 overlay to 301-and-240 for western Maryland (DC metro
as well as points further west, bordering West Virginia, (WV, BTW
since 2009, has been 304-overlaid-with-681), but there have never
been any formal implementation dates announced for this additional
Maryland 301/240/227 overlay. Of course, ten-digit dialing within the
state is mandatory for all local/EAS calling (1+ten-digits permissive
for local/EAS), so the groundwork is already in place.
> I suppose someday 202 will need relief, with the obvious choice
> being an overlay.
Some time back, it was thought that either 746 or 821 could have been
the relief area codes for future 202/DC relief. But neither will be
the case, since 202-746 and 202-821 are already now assigned as "POTS"
202-NXX c.o.codes in DC.
It seems that the future relief code for 202/DC might now be 771.
381 seems to be the future relief code for 703/571 in northern VA.
> However, somebody here on T-D once suggested a split of sorts:
> put the federal government in its own area code -- 666.
All kidding aside, 666 can NOT be a geographic NPA code. Remember that
NPAs with an identical digit in the second (B) and third (C) position
are RESERVED (or eventually assigned) for "special" functions. These
are SACs, the original definition (which I prefer) was "Special Area
Code", but the 1980s/forward definition is "Service Access Code".
800, 888, 877, 866, 855, etc. Toll-Free,
500, 533, 544, 566, etc. once for Personal Numbering
(but now the 5YY SACs are used for some indeterminable function!),
900, future 922, etc. PAY-PAY-PAY per-call,
700 LD-Carrier services,
and the 6YY range (600, 622, etc.)
all fit this criteria.
The entire 6YY range, including 666, with 600 being the only assigned
such SAC "in service" at present (since 610 was swapped for 600 in
1993), is reserved for Canada for their own special services.
ALSO, HAncock4 wrote:
> Speaking of Washington,
>
> Washington went dial around 1930. Washington grew somewhat during
> the New Deal as the alphabet soup agencies were formed, but then
> grew tremendously during WW II. (The Pentagon alone had about a
> 16,000 station PBX. See David Brinkley's excellent "Washington
> Goes to War".)
>
> Would anyone know what kind of switch type was used for Washington
> dial service, especially as the city grew?
Washington DC (eventually including the Maryland suburbs, but I don't
know about the northern Virginia suburbs) was one of the twenty-some
metro areas in the US, most of them being BIG urban metro areas, which
went dial in the 1920s/30s with Panel switching, latter supplemented
with #1XB, i.e., "Revertive Pulsing". There were no other areas in
the US that had such Panel/#1XB (RP) switching, and NONE in Canada
(except for the experimental "Lorimer" RP systems that didn't last
long, in the EARLIEST part of the 20th Century, in a few places in
Canada).
During the 1950s, #5XB (which was brand new as of 1948) began to be
added to both Panel/#1XB cities, as well as SXS cities, throughout
all of the US and Canada. #5XB was also used for manual-to-dial
conversions, as well as continued brand new installations of SXS for
manual-to-dial conversions, well into the 1960s-era.
Mark J. Cuccia
markjcuccia at yahoo dot com
Date: Fri, 16 Sep 2011 18:57:33 -0700 (PDT)
From: HAncock4 <withheld@invalid.telecom-digest.org>
To: telecomdigestmoderator.remove-this@and-this-too.telecom-digest.org.
Subject: Re: EXchanges (was: area code named beer)
Message-ID: <f1c03588-5c79-45ce-82d9-eb3aa2aa5cae@dp9g2000vbb.googlegroups.com>
On Sep 16, 10:24~am, HAncock4 <withh...@invalid.telecom-digest.org>
wrote:
> DDD required that all subscribers have a uniform ten digit number--
> three digit area code and seven digit local number. ~In 1950 a great
> many subscribers in smaller towns and cities had phone numers with
> three, four, five, or six digits, and all had to be converted to seven
> digits. ~This was a major undertaking that took years to complete.
P.S. Many times the "conversion" was accomplished at the same time a
town was converted from manual to dial, which was a major effort in
those years. Subscribers had to get used to a new phone number and
billing routing records had to be all changed, but there was no
equipment modification.
However, towns that were already dial had to be converted to be 7D.
In step-by-step offices this often meant adding a "digit absorbing"
selector. Say a town had five digit numbers, 5-xxxx and 6-xxxx and
the town was to become 345-xxxx and 346-xxxx. The switch would simply
absorb the initial 3 and 4. This meant that people within the town
would continue dialing five digits as they did before, only outsiders
needed all seven. In many small towns in isolated areas five digit
dialing continued well into the 1970s. It ended when more exchanges
were added as population grew.
I don't have any statistics, but I suspect DDD was not offered very
widely in the 1950s because the company was too busy expanding toll
line capacity and converting local exchanges to dial. I think the
Bell System was about 50% dial at the end of WW II, not sure of the
percentage in 1960. Anyway, the first step in providing DDD was to
providing operator direct dialing, which sped up call handling. That
meant adding toll trunk signalling systems for ringing and supervision
which was an effort in itself. (That signalling protocol would be
compromised later on by the "blue boxes".)
Even in the 1980s with DDD and TSP widespread, from time to time
operators still 'built up' toll calls by calling intermediate toll
centers and establishing the connection the old fashioned way.
Likewise, they also wrote charge tickets instead of AMA.
Other local exchange items that were necessary to provide DDD were
increasing the sender length in #1 crossbar and panel exchanges to
hold 10 digits, providing an 'exit' link in step by step exchanges,
and providing AMA (automatic message accounting) with automated or
operator calling number identification (ANI or ONI). AMA was
installed either in the local exchange or at a tandem or toll
switching office.
Would anyone care to comment on how all this stuff is handled by
modern exchanges today? Can a long distance company operator still
"build up" a call manually? Are there still long distance company
network managers watching their system for overloads and problems? Is
there still a big AT&T network control center in Bedminster? Thanks.
[public replies, please]
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