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Subject: History and Experience Concerning "Long Duration" Local Calls
Date: 11 Sep 90 21:20:10 EDT (Tue)
From: Larry Lippman <kitty!>

In article <> (David
Lesher) writes:

{can you time up a dial-up line all month?}

> An alarm distributor once told me that Sonitrol {sp} tried this. They
> offered an alarm system that triggered on loud noises inside the
> buildings at night. Then the alarm office could listen, mike by mike,
> to hear if it was an intruder, or a burping furnace.

> To do they, they used standard dialup lines, and kept them open all
> night, or all weekend. Ma took them up the court ladder, and won. I
> suspect the tariffs have some catchall phrase about "abnormal use" or
> such.

	I've not heard of the particular instance involving Sonitrol,
but I have heard of others.  In fact, some years ago I was personally
involved with this type of situation (details later in the article).

	This was indeed a matter of "concern" to the Bell System at
one time.  Most untimed (one-message-unit-per-call-regardless-of-length 
or true flat rate) subscriber line service for businesses was
eliminated during the 1970's, resulting in businesses being charged
for the actual length of calls.

	Prior to such changes in tariffs, a local call could exist for
a virtually unlimited time, tying up CO apparatus and interoffice
trunks without any revenue being produced.  The Bell System was
"concerned" because such usage could deprive it of revenue which
should otherwise arise from leased line circuits for say, data, alarm
or OPX purposes.  Some of this "concern" on the part of the Bell
System was no doubt brought on by the (then) comparatively recent
offering of telephone network interconnection devices, opening up new
possibilities for customers to utilizes apparatus which might deprive
the Bell System of revenue from the sale of its traditional products
and services.

	With the introduction of local message timing, the effective
"rate" for a continuous call usually exceeded the rate for a leased
line.  Therefore, the telephone company was "happy" with either
subscribers who made long, continuous calls or who obtained leased
lines - because either event generated revenue.  Quite frankly, I
don't believe that potential degradation of service to other customers
was ever a *true* concern, although it was certainly THE *voiced*

	So, the point is, in earlier days the telephone company was
not concerned because CO apparatus and interoffice trunks were tied up
per se, but because they had neither tariffs nor apparatus to permit
billing for such usage.  As a result, the telephone company would
refer to tariff provisions prohibiting a subscriber from "use of
service or facilities that would injuriously effect the efficiency of
the Telephone Company's plant, property or service." [actual tariff
quote] The intent, of course, was to force such a subscriber into
obtaining an appropriate leased telephone circuit.

	Today, in general, the telephone company extracts its "pound
of flesh" from every minute of almost every local business call, and
could care less about how long individual calls exist.  As an example,
in my local calling area based upon business rates, a month-long call
would cost around $ 300.00 - which is generally more than the monthly
cost of any comparable leased circuit.

	As a personal aside, in 1970 I designed and prototyped a
product which was intended to exploit untimed business calls to create
tie lines and OPX's for use with a telephone company-provided cord
PBX.  This product, which was called "Econo-Tie", would have saved
customers money by eliminating the cost of leased lines.  Using
combinations of burst and continuous inband tone signaling at 500,
700, 1100 and 1600 Hz, the device created supervisory, dial and
ringing signals over a dialed-up telephone circuit.  One device was
required at each customer location.  

Each pair of devices could be optioned to provide any one of the
following: OPX, manual ringdown tie line, automatic ringdown tie line,
and one-way dial repeating tie line.  The product was only intended
for use with cord PBX's, such as 551, 552, 555 and 608 - either as a
manual PBX or as a cord board in front of a 701, 710 or 740 SxS PABX.

The product was intended to mount next to the cord PBX, and all
connections were made using the PBX cords.  The device tied up one
cord circuit and one CO trunk jack of the PBX at all times to create
the CO line connection, with supervisory lamps indicating when the
connection was established, or whether it had failed and required
redialing.  The device provided both station and CO trunk jacks for
use with the cord board, and a jack for customer-provided 500-type
sets when used for OPX service.  In OPX mode, dialing to establish the
CO line circuit could only be accomplished at the PBX end.

	While the above device may sound complex, the control logic
and timing was actually simple (if taken step by step), and was
provided using only about ten DTL integrated circuits.  The most
expensive part of the product design was the -48 volt, 20 Hz ringing
and logic power supply modules.  Isolation from the telephone circuits
was maintained using transformers and relays.  Seven miniature AE
relays were used to provide: CO line CPC supervision, PBX cord
supervision sense, PBX cord supervision control, battery feed and loop
control, dial pulsing, PBX or station ringing control, and PBX or
station ring trip detect.  Two fabricated neon lamp optocouplers were
used for ringing detection.  

Today's solid-state optoisolators would have vastly simplified circuit
design and reduced cost, but they were not as yet "in" in 1970.
Savings in cost could also have been achieved if the product were made
specific to each end of each operating mode, but the intention at the
time was to build one and one only physical product which was
"hermaphroditic" in nature and could be optioned as necessary.  The
product was admittedly overdesigned, but was intended to be as
reliable as possible and to sell for $ 1,600.00 per pair - which
represented a typical two year payback for its intended customers.
Implementation of the device would have not only eliminated tie line
IXC mileage and local CO loop charges, but would have eliminated PBX
charges for tie line termination apparatus.  In 1970, this was a
*very* attractive payback interval for, say, the retail store

	My original prototype versions had no amplification to
compensate for circuit loss (it was still quite usable under most
circumstances).  I had actually incorporated a Transcom negative
impedance repeater in the prototypes to provide about 3 dB of gain at
each end, but it was not stable at even this low of a gain setting
over the wide range of loop impedance conditions that were
encountered.  The repeater was therefore bypassed during field
testing.  Had there been a final design, it would have utilized a more
stable hybrid-type repeater.

	Another loophole exploited by this product was that there was
no permanent electrical connection to any telephone company apparatus,
so that it could be disconnected (and hidden :-) ) at a moment's
notice.  There was also no tariffed "interconnecting unit" to go
between a PBX cord and customer provided equipment, so this fell
through a crack with respect to interconnection "protection"

	I ran two sets of prototypes for about three months with some
department stores.  Retail stores were notoriously *cheap* when it
came to telecommunications costs, would do almost anything to save
money, and were my primary target market.  During this test phase in
early 1971, I succeeded in capturing the undivided attention of New
York Telephone - as one might imagine :-).

	New York Telephone management was not amused at the prospect
of someone actually manufacturing and marketing this type of a
product.  Consequently, New York Telephone initiated a 3-pronged
attack to "dissuade" me from further pursuit of this product:

(1)	Threats and Intimidation ... "We will summarily disconnect the
	telephone service of any customers caught using this device.
	How would you, Mr. Engineer-turned-Entrepreneur, like to face
	the consequential liability for that?"

(2)	Impassioned Plea for Fairness ... New York Telephone was aware
	that at the time I worked as a consulting engineer who primarily
	handled engineering requirements of a stable of small independent
	operating telephone companies.  New York Telephone appealed to
	my sense of "fair play", in that I would be a "traitor" to the
	operating telephone company industry should I continue with plans
	to manufacture and market this device.

(3)	Changing Tariffs ... New York Telephone revealed various plans
	and proposed tariffs which would be effective within the next two
	years, with such actions resulting in introduction of message
	timing for all major cities in New York State.  The introduction
	of local message timing would make this product largely
	Reason #3 (with a little help from Reason #1) persuaded me to
drop the project.  Reason #2 did indeed make me feel bad - for all of
thirty seconds. :-)

	Telecommunication "progress" was much slower twenty years ago.
The thought of marketing a product that would be unusable in as little
as two years (other issues notwithstanding) did not seem at the time
to make good business sense.

	As it turned out, the full implementation of New York
Telephone's local message timing plans for business service took more
like six years rather than the two years that they had represented.
Yes, they lied. :-) I have, on occasion, wondered what would have
happened had I proceeded with my original plans for this product and
tangled with "Ma" over the issue.

Larry Lippman @ Recognition Research Corp.
VOICE: 716/688-1231 || FAX: 716/741-9635  {utzoo||uunet}!/      \aerion!larry

Subject: Larry Lippman, R.I.P.
Date: Fri, 24 Jan 92 13:50:06 PST
From: Steve Elias <>

[Moderator's Note: Steve Elias passed along this sad message from
Marvin Minsky.  I've not had an opportunity to confirm this, but
wanted to get the information out as soon as possible. Long time
Digest readers will remember Larry quite well and his many very
interesting articles here.  PAT]

 From: (Marvin Minsky)
 Subject: In Memoriam: Larry Lippman
 Organization: MIT Media Laboratory
 Date: Fri, 24 Jan 1992 04:43:38 GMT

I regret to tell you that Larry Lippman suddenly passed away.  (Heart
attack, no warning whatever.)

I never met him myself, but I tremendously appreciated his thoughts
and ideas on this network.  It meant a lot to me -- and I'm sure to
hundreds of you, as well -- to feel that if I had any question at all,
about the most exotic chemical (or electronic) issues -- I would
always know a resource to try.  Just type a little note, with no
effort, and get a wise reply the next day.
And then no words from him for such a long time that I could not
resist breaking the rules -- as in "True Names" -- of invading another
person's private life.  His wife Cindy told me what had happened, and
that he was only 42, and went to college at the age of 12 (as you
might have guessed) and a few things like that.

It isn't fair.

        Marvin Minsky

Steve Elias,      617 932 5598

[Moderator's Note: We shall miss him. I spoke to him only about two
months ago for two hours one evening on the phone.   PAT]

From: (Barry Ornitz)
Subject: Re: Larry Lippman: In Memoriam
Organization: Eastman Kodak Company, Eastman Chemical Company Research Labs
Date: Tue, 28 Jan 92 23:43:05 GMT

In article <> minsky@media. (Marvin Minsky) writes:

> I regret to tell you that Larry Lippman suddenly passed away.  (Heart
> attack, no warning whatever.)

I too would like to say a few words about Larry ...

I have noted that some of the posts following the thread of the death
of Larry have deteriorated into jokes about email.  At first I was a
little offended, but then I thought back over the years I had known
Larry and concluded that with his excellent sense of humor he would
have enjoyed them.  As far as email is concerned, Larry has probably
already rigged a UUCP feed direct to heaven!

I was fortunate to have known Larry for several years both
professionally and personally.  As we both had backgrounds in
chemistry (ChE for me), electronics, and instrumentation, it was
natural for us to meet on the Net.  Our email messages eventually grew
into occasional telephone calls.  I found Larry to be witty, extremely
intelligent, and a warm, caring person.  He also liked cats!  (But I
used to kid him that I was owned by more cats than he was.)

Larry's knowledge was practical as well as theoretical.  His postings
were gems: concise, accurate, and easy to understand.  I think he did
more than anyone else in the early days of the sci.chem newsgroup to
keep the group active and interesting.  You could also see Larry's
wisdom scattered in a number of other groups too.  (I added the
telecom group to this posting because of his frequent posts about
telephone systems.)  He also was known to slip in some good natured
humor into his posts.

I will remember Larry's serious posts on chemical and laboratory
safety; but I also remember his suggestion to me that we gold-plate
Hubbell twist-lock power connectors and sell them to the as $500 speaker connectors for the "golden-eared".
I will always cherish the telephone call from him as he was still
laughing over my posting on monomethyl,lirpanoic butyrate as an
improved snake oil for CD coating.

I hope the USENET community will reflect on how Larry Lippman helped
many readers over the years.  As far as the jokes go, I know Larry
will be laughing!

If anyone is seriously thinking of taking up a collection for a
scholarship in Larry's name, I will be proud to contribute.

Barry L. Ornitz

[Moderator's Note: Not many people here are aware that it was
complaints by Larry which led to the Nynex purchasing scandal a few
years ago. His company was one which got shafted by Nynex in the deal
where they were purchasing things at inflated prices from themselves.
When {Newsday} first  broke the story, Larry was mentioned as one of
the people who instigated the investigation.   He called me on the
phone several times last summer inviting me to come and visit him at
his home in Rochester, NY but I had to decline because of the problem
I was having with my foot at the time. I'm sorry now I did not take
him up on his offer. He was in the process of dismantling the local
Western Union office after WUTCO had abandoned it and turned it over
to him to get rid of.  (Literally! They walked out and left everything
in place, hiring Larry and a friend of his to dismantle it all and get
rid of it.)   PAT]

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