TELECOM Digest     Tue, 3 May 94 12:26:00 CDT    Volume 14 : Issue 196

Inside This Issue:                          Editor: Patrick A. Townson

    The Great Clipper Debate - 5/9/94 (Dave Banisar)
    Telecom in China (Todd Allmendinger)
    "The President's Analyst" is on AMC Tonight! (Jim Maurer)
    Re: Radio Frequency Interference on Residential Line (puma@netcom.com)
    Re: Radio Frequency Interference on Residential Line (Carl Oppedahl)
    Re: Radio Frequency Interference on Residential Line (Rich Osman)
    Re: AT&T Public Phone 2000 Probably Dead (Edwin Green)
    Re: AT&T Public Phone 2000 Probably Dead (Hans-Gabriel Ridder)
    Re: AT&T Public Phone 2000 Probably Dead (Rob Levandowski)
    Re: NPA Optional in 818 - it Works! (Rich Greenberg)
    Re: NPA Optional in 818 - it Works! (Bill Hofmann)
    Re: 16 Mbps Modem for Real? (Christian Weisgerber)
    Re: 16 Mbps Modem for Real? (John Lundgren)
    Re: GM-Hughes 500 Channels (puma@netcom.com)
    Re: Source of 25 Pair AMP Connector to RJ11 Patchboard Needed (J.
Lundgren)
    Re: Source of 25 Pair AMP Connector to RJ11 Patchboard Needed (J.
Hennigan)

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----------------------------------------------------------------------

Date: Mon,  2 May 1994 18:17:02 +0000
From: Dave Banisar <epic@cpsr.org>
Subject: The Great Clipper Debate  5/9/94


                      The Great Clipper Debate:
              National Security or National Surveillance?

Sponsored by:  The Georgetown University Law Center Space Law Group
               and Communications Law Forum

In Coordination with: The George Washington University Institute for
Computer and Telecommunications Systems Policy, the Association for
Computing Machinery Special Interest Group for Computers and Society,
and the American Bar Association Criminal Justice Section.

Date and Time:    May 9, 1994, at 7:30 p.m.

Place:            The Georgetown University Law Center(Moot Court Room)
                  600 New Jersey Avenue, N.W., Washington, D.C.

     The Administration, through the Department of Justice and the
National Security Agency, has proposed a standard encryption algorithm
for both the public and commercial marketplace, with the goal of
making this algorithm the method of choice for persons wishing to
encode their telephone and other voice and data communications.  The
FBI and the NSA are concerned that the increasing availability, and
affordability, of encryption mechanisms will make it difficult and in
some cases impossible for law enforcement and intelligence agencies to
tap into and to understand the communications of criminals and other
pertinent groups.  This proposal has become known as the "Clipper
Chip," in that it would be implemented by the voluntary insertion of a
computer chip into telephone, fax machine, and other communications
systems.

     The Clipper Chip has generated considerable controversy.
Opposing it are various civil libertarian groups, as well as
telecommunications companies, software and hardware manufacturers, and
trade associations.  The debate has raged behind closed doors, and
openly in the press.

     On Monday, May 9, at the Georgetown University Law School, a
round table debate will take place on this controversy.  The
participants represent both sides of the issue, and are illustrative
of the various groups which have taken a stand.  The participants are:

        Dorothy Denning, Chairperson of the Computer Science Department
        of Georgetown University
         
        Michael Godwin, Legal Counsel of the Electronic Frontier
        Foundation;
         
        Geoffrey Greiveldinger, Special Counsel to the Narcotic and
        Dangerous Drug Section of the U.S. Department of Justice;
         
        Michael Nelson, of the Office of Science and Technology Policy
        of the White House;
         
        Marc Rotenberg, Director of the Electronic Privacy Information
        Center; and
         
        Stephen Walker, President of Trusted Information Systems, Inc.,
        and a former cryptographer with the National Security Agency
         
     In addition, there will be two moderators: Dr. Lance Hoffman,
Professor of Electrical Engineering and Computer Science at The George
Washington University, and Andrew Grosso, a former federal prosecutor
who is now an attorney in private practice in the District of
Columbia.

     The program will last approximately two and one half hours, and
will be divided into two parts.  The first half will offer the panel
the opportunity to respond to questions which have been submitted to
the participants beforehand; the second will present the panel with
questions from the audience.

     There is no charge for this program, and members of the public
are encouraged to attend. Reservations are requested in advance, and
should be directed to one of the following individuals:
    
   - C. Dianne Martin, Associate Professor, Department of Electrical
   Engineering and Computer Science, The George Washington University,
   Phillips Hall, Room 624-C, Washington, D.C. 20052; telephone: (202)
   994-8238; E mail: diannem@seas.gwu.edu
    
   - Sherrill Klein, Staff Director, ABA Criminal Justice Section,1800
   M Street, N.W., Washington, D.C.  20036; telephone: (202) 331-2624;
   fax: (202) 331-2220
    
   - Francis L. Young, Young & Jatlow, 2300 N Street, N.W., Suite 600,
   Washington, D.C. 20037; telephone: (202) 663-9080;  fax: (202)
   331-8001
    
   Questions for the panelists should be submitted, in writing, to one
   of the moderators:
    
   - Lance Hoffman, Professor, Department of Electrical Engineering and
   Computer Science, The George Washington University,  Washington,
   D.C. 20052; fax: (202) 994-0227; E mail: ictsp@seas.gwu.edu
    
   - Andrew Grosso, 2300 N Street, N.W., Suite 600, Washington, D.C.,
   20037; fax: (202) 663-9042; E mail: agrosso@acm.org
    
------------------------------

Date: Tue, 3 May 1994 08:46:23 MST
From: Todd Allmendinger <24874@ef.gc.maricopa.edu>
Subject: Telecom in China


 I am working on a project concerning leased line digital
telecommunications, using satellite links.  I understand a joint
equity venture is not possible, however a joint revenue sharing
agreement is permitted, and in use by several companies.

        I am interested in talking with some telecommunications
persons in China. Either from the MPT, regional local PTT or some of
the other minitries such as Minstry of Electronics who operate their
own networks, CHINAPAC etc.

        I will be in Harbin for June and July and in Bejing for a few
days in Aug. I plan to attend the information technology conference in
Beijing.

        I would also like to find out about upcoming conferences
either in China or outside of China which will talk about telecommunicat-
ions in China. Again these could be related to MPT organizations or
Other Ministries that have their own networks.
 
Please respond directly to my E-mail address. Thank you.
  
      
Todd Allmendinger    24874@ef.gc.maricopa.edu

------------------------------

Subject: "The President's Analyst" is on AMC Tonight!
Date: Tue, 3 May 1994 09:41:03 PDT
From: Jim Maurer <jim@specialix.com>


The movie "The President's Analyst" will be on the cable channel AMC
tonight at 9:30 pm (at least in California, check your local listings).
I'm sure it'll be on again, but I don't know any dates or times.

Be sure to watch it and find out how the Bell System took over control
of the government in the 1960's!!!!  Classic Telecom entertainment!


Jim Maurer          Specialix Inc.   
jim@specialix.com   +1-408-378-7919  

------------------------------

Date: Mon, 2 May 1994 18:42:52 -0700
From: puma@netcom.com (puma)
Subject: Re: Radio Frequency Interference on Residential Telephone Line


In article <telecom14.191.12@eecs.nwu.edu> is written:

> My home is wired for two residential telephone lines.  Because of my
> proximity to an am radio transmitter (am 1550khz), many of my audio
> and telephone devices suffer from "radio noise", from that one station
> only though.  Some days it is worse than others, some days there is no
> interference at all.
> The local telco has installed several blue capacitors(?) at the demark box
> on my house.
> Please respond via e-mail to ld18@clark.edu.

The problem with radio-frequency energy actually becomes a problem
when it ends up at "a something" that demodulates it, then you hear
the signal.  One potential 'something' is anything containing
semiconductor electronics.  Another 'something' is any kind of a poor
connection, which sometimes acts as a diode.

You can fight this by reducing the signal.  Capacitors/RF filters at
the demarc and capacitors across the carbon mike in a telephone (it's
non-linear and will demodulate RF) are good starts.  A ferrite choke
(donut) placed near the telephone, with the line cord making a couple
turns through it, is another common tactic.  Non-electronic phones
often are less of a problem (although less functional) than electronic
ones.

Visit your local amateur radio / electronics shop for parts and
advice.  Good luck!


puma@netcom.com

------------------------------

From: oppedahl@panix.com (Carl Oppedahl)
Subject: Re: Radio Frequency Interference on Residential Telephone Line
Date: 3 May 1994 00:26:02 -0400
Organization: PANIX Public Access Internet and Unix, NYC


In <telecom14.191.12@eecs.nwu.edu> Dirk Menzel <ld18@clark.edu> writes:

> I have had all of the affected telephone devices modified by their
> respective manufacturers ... the problem persist on a recently puchased
> Panasonic KXT3175, two-line, Easa-Phone.

> The local telco has installed several blue capacitors(?) at the demark box
> on my house.

> I have tried to eliminate the Panasonic telephone as the culprit by
> putting it in a metal breadbox (really!!!), with no success.

This was unlikely to have helped.

> I believe that the noise is entering the line via a TP four-conductor
> cable strung along the outside of my home.

Could be.

> At this point I am open to suggestions.  Might I be able to install a
> filter (to filter out mainly 1550khz) right at the telephone?  

I would consider installing low-pass filters at many locations, to
break up your lines so that they are unlikely to present any resonant
lengths.

> (I use one of my lines for voice and modem.)  A commercially available 
> inline filter (#Z100B1), besides being a single line device, did not 
> have any effect.

You can filter each line (red/green and yellow/black) separately.

Pick up the May issue of QST.  It has ads in the back from companies
that sell phone line filters, and it has an article on the FCC testing
phones tht turn out to be bulletproof against RF interference.


Carl Oppedahl AA2KW    Oppedahl & Larson (patent lawyers)
Yorktown Heights, NY   voice 212-777-1330  

------------------------------

Date: Mon, 2 May 94 18:13:20 CDT
From: ROsman@swri.edu
Subject: Re: Radio Frequency Interference on Residential Telephone Line


> My home is wired for two residential telephone lines.  Because of my
> proximity to an am radio transmitter (am 1550khz), many of my audio
> and telephone devices suffer from "radio noise", from that one station
> only though.  Some days it is worse than others, some days there is no
> interference at all.

This is an increasingly common problem.  Newer more electronic devices
have more opportunities for rectification and internal amplification.
This makes them more susceptable to this kind of interference.  I have
an AM Spanish-language station 3/4 of a mile from the house -- same
problem in my bulletprook ole' 1A2.  The problem is occurring in the
music-on-hold receiver or amp.

> I have had all of the affected telephone devices modified by their
> respective manufacturers ... the problem persist on a recently puchased
> Panasonic KXT3175, two-line, Easa-Phone.

**IF** the problem appears on both lines equally, then it is probably
the Easa-Phone.  My guess is that the variation in the problem
correlates to wet weather or wet ground.  If you are powering the
phone off the wall (not the phone line), see if you can run it off a
battery temporarily.  Unplugging the phone lines may tell you
something, but I'll bet they need to be plugged in to see the problem,
even if it's coming in the power line.  It is possible that it's
sneaking in the power connection.  There are some off-the-shelf
filters available to add addtional filtering in the line.  I'll have
to see what I can spot.  I'll be you get other notes suggesting brands
and sources.

How many devices are on the line with the Easa-Phone?  Does the
problem appear on both lines?  The bad news is that the problem may
actually be occurring in another device and only appears on
Easa-Phone.  If the problem is not on both lines, you might try
swapping lines into the Easa-Phone, and try swapping devices between
lines.

> The local telco has installed several blue capacitors(?) at the
> demark box on my house.

*Ahem*, condensers my good man!  These really are caps, and are good
for certain applications, but I'm found them to be really useful only
when installed inside early (read: non-electronic hybrid) 500/2500
sets.  Since you have already said that you've had the Panny modified
by them, I'd try external filtering at the phone.  The blue cans are
cute, but I don't hold a lot of hope for them.  A good commercial
filter is the best bet.

> I have tried to eliminate the Panasonic telephone as the culprit by
> putting it in a metal breadbox (really!!!), with no success.

It's unlikely that this will help.  The problem is probably coming in
the phone or power line.  The only way this *might* help is if the
problem was occurring in the phone itself, and them you'd need to be
sure the grounds were all correct and that the lid really was grounded
too.  Try putting an AM radio tuned to 1550 in the breadbox and see
what happens.  Try tuning another strong local station.

> I believe that the noise is entering the line via a TP four-conductor
> cable strung along the outside of my home.

Why do you believe this?

> At this point I am open to suggestions.  Might I be able to install a
> filter (to filter out mainly 1550khz) right at the telephone?  (I use

Right at the phone, or better yet inside are the only really useful
locations in this kind case.

> one of my lines for voice and modem.)  A commercially available inline
> filter (#Z100B1), besides being a single line device, did not have any
> effect.

Whose part number is that and what were it's specifications?  Many of
these are designed to combat higher frequency problems (like CB) and
are inneffective at AM broadcast frequencies.

> Any help would be greatly appreciated.  I am fairly technically and
> mechanically competent and could handle minor electrical modifications
> with limited instructions.

One thing I'd try is to e-mail info@arrl.org and ask them for their
lastest RFI brochure.  It's written from the standpoint of a ham
trying to solve his own problems and prevent problems with and for
neighbors.  I think there's also a note in the archives under RFI or
somesuch.


Oz@SwRI.edu  (Rich Osman) (210) 522-5050 (w)  (210) 699-1302 (h;v/msg/fax)

------------------------------

From: egg@inuxs.att.com (Edwin Green)
Date: Tue, 3 May 94 07:41:47 EST
Subject: Re: AT&T Public Phone 2000 Probably Dead
Organization: AT&T


In article <telecom14.192.5@eecs.nwu.edu> is written:

> (Newcomers: The Public Phone 2000 was a venture attempted by AT&T a
> few years ago.  Essentially, computer terminals were placed at many
> international airports in the U.S.  With a calling card, you could
> place calls anywhere there was a modem, without having to worry about
> bringing your own laptop and somehow connecting it to a pay phone.
> Unfortunately, it turned out the phone terminals were not tariffed,
> so AT&T had to disable the terminal feature pending approval.)

> I had the chance to spend a couple of hours at the St. Louis International 
> Airport this weekend, and I saw a couple of AT&T Public Phone 2000
> booths, so I decided to check them out.  Alas, what I found were plain
> old pay phones.  I suppose this means that AT&T has decided to give up.

> [TELECOM Digest Editor's Note: That's a shame, because the 2000's were
> a very useful service. Too bad it did not work out.   PAT]

The reports of our death are premature!  We received partial approval
from the FCC to turn on terminal emulation, but not full approval.  We
have been waiting since March to turn it back on.  It could be any day
or it could be months.  At any rate, when we get approval I will let
you know.


Edwin G. Green
AT&T Bell Laboratories          Indianapolis, Indiana, USA
INH 1A-519                      317-845-3659
egg@inuxs.att.com


[TELECOM Digest Editor's Note: Please do!  I'll be happy to post it here
and let everyone know the 2000 phones are back in full service.  PAT]

------------------------------

From: ridder@zowie.zso.dec.com (Hans)
Subject: Re: AT&T Public Phone 2000 Probably Dead
Date: 3 May 1994 16:37:27 GMT
Organization: Digital Equipment Corporation - DECwest Engineering


In article <telecom14.192.5@eecs.nwu.edu> John C. Fowler <fowlerc@magellan.
Colorado.EDU> writes:

> I had the chance to spend a couple of hours at the St. Louis International 
> Airport this weekend, and I saw a couple of AT&T Public Phone 2000
> booths, so I decided to check them out.  Alas, what I found were plain
> old pay phones.  I suppose this means that AT&T has decided to give up.

I was in the Alaska Airlines terminal at the Seattle-Tacoma airport
two weeks ago, and saw a couple of Public Phone 2000's *with
keyboard*.  I didn't have time to check them out ... I assume they
were working since after the tariff problems all the keyboards seem to
have been removed.

> [TELECOM Digest Editor's Note: That's a shame, because the 2000's were
> a very useful service. Too bad it did not work out.   PAT]

Since John based his remarks on his experience in one airport, and not
from any offical announcements from AT&T, it's probably a bit premature 
to be speaking in the past tense, don't you think?


Hans-Gabriel Ridder <ridder@rust.zso.dec.com>
DECwest Engineering, Bellevue, Washington, USA

------------------------------

From: rlvd_cif@uhura.cc.rochester.edu (Rob Levandowski)
Subject: Re: AT&T Public Phone 2000 Probably Dead
Organization: University of Rochester - Rochester, New York
Date: Tue, 3 May 94 00:41:11 GMT


It strikes me as odd, too ... considering that the 2000s have been
very visible in some episodes of the NBC-TV show "Viper" lately as
videophones -- logo, name and all -- I had been wondering if AT&T was
considering a new use for them. Especially considering the way AT&T
has been pushing videophone technology of late. One would imagine it
would not be impossible to retrofit the 2000s with video codecs ...
Perhaps not cost-effective, but possible.


Rob Levandowski
Computer Interest Floor associate / University of Rochester
macwhiz@cif.rochester.edu 

------------------------------

From: richgr@netcom.com (Rich Greenberg)
Subject: Re: NPA Optional in 818 - it Works!
Organization: Netcom Online Communications Services (408-241-9760 login:
guest)
Date: Mon, 2 May 1994 22:36:32 GMT


In article <telecom14.191.8@eecs.nwu.edu> justfred@netcom.com (Fred
Heald) writes:

> To my surprise this morning I found that a feature I've been asking for 
> forever finally works!

[...]
> Netcom) I accidentally dialed the 1-818, and the call went through!
 
> Since I'm in PacBel land, I'm hoping they've implemented this all over
> the area.  FINALLY! and yet with no fanfare or even notice -- I guess
> they'd be admitting a mistake.

I am in the 310 part of Pa Bell, and it worked here also.  Thanks Pa.


Rich Greenberg            Work: ETi Solutions, Oceanside & L.A. CA
310-348-7677
N6LRT   TinselTown, USA   Play: richgr@netcom.com                 
310-649-0238

------------------------------

From: wdh@netcom.com (Bill Hofmann)
Subject: Re: NPA Optional in 818 - it Works!
Organization: NETCOM On-line Communication Services (408 241-9760 guest)
Date: Tue, 3 May 1994 03:04:02 GMT


This has been the case in 510 since October.


Bill Hofmann    wdh@netcom.COM
Fresh Software and Instructional Design +1 510 524 0852

------------------------------

Date: Mon, 02 May 1994 22:30:00 +0200
From: naddy@mips.ruessel.sub.org (Christian Weisgerber)
Subject: Re: 16 Mbps Modem for Real?


In comp.dcom.telecom was written:

> Has anyone heard of a small company called Digital Compression
> Technology (DCT)?  It claims it can move 16 Mbps of various kinds of
> data down a regular telephone line (yes, that's 16 MEGABITS per
                      ^^^^^^^^^^^^^^
> "DCT technology lets telephone wire simultaneously carry [ a lot ]
                       ^^^^^^^^^^^^^^
> Is this for real or is DCT a couple of engineering students with some
> vaporware, a fax machine, and a gift for self-promotion?

Quite possibly this is real. However, you're completely
misinterpreting the achievement. Those people move 16Mbps over
telephone type cabling, comparable to, say, Twistet Pair Ethernet
(10Base-T). They're not doing this over the traditional PSTN. There's
no reason to get particularly excited.


Christian 'naddy' Weisgerber, Germany         naddy@mips.ruessel.sub.org

------------------------------

From: jlundgre@kn.pacbell.com (John Lundgren)
Subject: Re: 16 Mbps Modem for Real?
Date: 02 May 94 18:36:33 GMT
Organization: Pacific Bell Knowledge Network


I thought CDDI and fast ethernet were already here.  In this case, the
16MBPS modem sounds more like a CSU/DSU, or TA.  If so, then the phone
co. would provide service at whatever speed your heart and wallet
desires.  If you want 45MBPS, then they will provide it.  They may
decide the most practical solution is to provide fiber to your
location, or a microwave link if it's more cost effective.  You hook
up your 16MBPS thingy, and away you go.

------------------------------

From: puma@netcom.com (puma)
Subject: Re: GM-Hughes 500 Channels
Organization: organized?? me?
Date: Mon, 02 May 1994 21:51:14 GMT


In article <telecom14.182.8@eecs.nwu.edu>, A. Padgett Peterson
<padgett@tccslr.dnet.mmc.com> wrote:

> A couple of months ago Hughes was advertising for technicians to
> service their new small-dish satellite TV system (500 channel?). Does
> anyone know what the status is, when it will become available, or have
> a contact phone or E-Mail number ? Reply to: padgett@tccslr.dnet.mmc.com

 From the Friday, April 22nd, {Milwaukee Journal}
 
   The DBS dishes are small, about 18 inches in diameter vs. 6 to 10
feet across for conventional satellite dishes.  DBS dishes are also
less expensive.  Suggested retail prices range from $700 to $900,
quite a bit lower than the $2,000 to $3,000 cost of the larger dishes.

   They will be manufactured by Thomson Consumer Electronics and sold
under the RCA brand name.

   Up to 150 channels will be available through DBS, including most
major cable channels and premium stations like HBO.

   Programming will be provided by DirecTV, a unit of GB Hughes
Electronics, and United States Satellite Broadcasting.  Users will
have to pay monthly fees ranging from $22 to $35, depending on the
channels they want.


puma@netcom.com

------------------------------

From: jlundgre@kn.pacbell.com (John Lundgren)
Subject: Re: Source of 25 Pair AMP Connector to RJ11 Patchboard Needed
Date: 03 May 94 10:11:30 GMT
Organization: Pacific Bell Knowledge Network


Joseph McGuckin (josephm@pumasillo.San-Jose.ate.slb.com) wrote:

> I'm looking for a rack mountable patchboard that accepts a 25 pair AMP
> connector and fans it out to 25 RJ11's.

> Joe   josephm@San-Jose.ate.slb.com
                ^^^^^^^^

You look like you're within a reasonable distance from Fry's
Electronics.  Check them out.  The one here in Orange County has a
fairly good supply of stuff such as octopus cables, etc. for telecomm.

Best of success.

------------------------------

From: jay@coyote.rain.org (Jay Hennigan)
Subject: Re: Source of 25 Pair AMP Connector to RJ11 Patchboard Needed
Date: 03 May 1994 06:15:01 -0700
Organization: Regional Access Information Network (RAIN)


In article <telecom14.184.8@eecs.nwu.edu> josephm@pumasillo.San-Jose.
ate.slb.com (Joseph McGuckin) writes:

> I'm looking for a rack mountable patchboard that accepts a 25 pair AMP
> connector and fans it out to 25 RJ11's.

Try Allen-Tel (sold by Graybar) for their model AT125-SM.  This does
what you want but it's surface-mount.  Bolt one (or more) to a blank
rack panel and you're done.
 

Jay Hennigan   jay@rain.org

------------------------------

End of TELECOM Digest V14 #196
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