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TELECOM Digest     Tue, 18 Jan 94 01:43:00 CST    Volume 14 : Issue 38

Inside This Issue:                          Editor: Patrick A. Townson

    CA State Report on LA Quake (Mike King)
    Los Angeles Earthquake, January 17 (Nigel Allen)
    More on the LA Earthquake (Robert L. McMillin)
    FYI AT&T Reduces LA Quake Services to 203, 310, 805 and 818 (Dan Arthur)
    Still Alive (Lauren Weinstein)
    Book Review: "Basics Book of Frame Relay" by Motorola (Rob Slade)
    DBS Satellite Services in Europe (Alfredo E. Cotroneo)
    Case History of a Phone Rip-Off (Part 1) (David L. Kindred)
    Cost of GTE Dialup Lines (Charles M. Hatcher)
    Shannon and Echo Canceller Protocols (Arnim Littek)
    More on Communication Over Power Lines (Michael Duane)
    V.32vis -> Bell_102 Due to CO Data Compression (Ross Porter)

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

From: [e-mail] (Mike King)
Subject: CA State Report on LA Quake
Date: Mon, 17 Jan 1994 16:06:01 PST


Passed along FYI:

   FROM: Governor's Office of Emergency Services, Sacramento

STATE OFFICE OF EMERGENCY SERVICES
STATUS REPORT
AS OF JANUARY 17, 1994, 1130 HOURS
SAN FERNANDO VALLEY EARTHQUAKE

1.      Proclamations/Declarations

        1. Local Declarations - County & City of Los Angeles, City of
                Hawthorne, County of Ventura
        2. Governor's Proclamation of a State of Emergency - County of Los
                Angeles

2.      Disaster Assistance Programs/Facilities

3.      Dead/Injured

        3 - 19 fatalities reported--not confirmed.

4.      Evacuations

        (See medical)

5.      Damages/Incidents

        OES Fire reports 70+ structures involved or down from fire.  All
fires under control.

        LA City  - 100 incidents reported.  Numerous building collapses;
mainly in north area.  Ranging from single family homes to larger
structures including an apartment building and Northridge shopping mall.
People trapped.  Partial collapse to pancaking.

        LA County - City of El Monte--unreinforced masonry moderate damage.
Cities of Sierra Madre and Alhambra--broken glass in business districts.

        Ventura County - Fillmore hardest hit; partial collapse of Fillmore
Hotel.  Petro chemical plant at SR 126 and Santa Clarita; potential
chlorine release.  Fire at El Dorado Mobile Home Park, Fillmore.

        Saugus - 1,000 hydrocloric acid and 500 gallon of sodium
hyperchloride spill.

        Lake Castaic - Ruptured tank - crude oil spill with one-mile plume
(unconfirmed).

        Valencia - pipeline rupture, crude oil.

        Oil flowing into Santa Clara River.  Three more pipeline leaks in
Newhall, Pyramid Lake, and Quail Lake (I-5 & SR 138).  Train derailment
5,000 gallon acid sulfuric acid - Northridge.

        State Facilities--Have inspected three major state buildings.  Los
Angeles State Building and Ronald Reagan Building - no power; Long Beach
State Building - no reports of damage.  Three sites damaged (Santa Monica,
Culver City, and Inglewood).  California Aqueduct overpassing cracked at
Silverwood Lake to Bakersfield.

        Counties of Orange, San Bernardino, San Diego, Riverside, Santa
Barbara, Imperial, Mono, Inyo, San Luis Obispo- Report no major damage.

6.      Care & Shelter

        American Red Cross identifying shelter sites; have experienced
power problems at their Headquarters in Los Angeles.

         4 shelters open--Sylmar High School; Canoga High School; Simi
Valley High School; Oxnard Armory.

7.      Medical

        Inspectors are in the field.  Problems appear to be power outages
and broken glass.

        L.A. County reports three hospitals with major damage (Holy Cross,
Panorama City, VA Sepulveda); patients evacuated.  State Fire Marshal
reports Holy Cross appears most impacted.  Major problems for hospitals are
no water; on emergency power with approximately 4 hours of emergency fuel
left.  Injury reports from these hospitals are minor.

        EMSA reports emergency radio net to hospitals has broken down
twice.  Have received reports of 6 or 7 severely impacted hospitals.

8.      Utilities

        Reported oil pipeline rupture in Valencia; spill only, no ignition.

        Southern California Gas - Numerous interruptions at their
facilities; assembling crews and moving them into critical areas;

        Southern California Edison - Numerous power outages; detailed
report to follow.

        Telecommunications - AT&T and GTE report major switch problems;
will be coordinating movement of equipment into critical areas.  Local
communication service out in Pacoima due to structural damage to Pac Bell
switching center.

        Water - LA Dept. of Water and Power reports aqueduct broken in San
Fernando Valley.  Trunk line breaks in the area.  Large water tank has
collapsed and another has sustained minor damage.

9.      Road Net

        See Caltrans report

10.     Air Space/Facilities

        Los Angeles International (LAX) and Long Beach Airports closed for
                inspection.
        Orange County - All airfields open.

11.     Other critical information


12.     EOCs and other facilities activated
        State Operations Center; Southern Region EOC
        CHP  Emergency Response Center - Headquarters and Southern
                Division.
        State Police EOC - Headquarters
        CDF EOC - Headquarters
        Caltrans EOC - Headquarters
        Office of Statewide Health Planning & Development (OSHPD) EOC -
                Headquarters
        DHS Emergency Coordination Center - Headquarters
        Dept. of Fish & Game EOC - Headquarters
        FEMA Region IX EOC, Disaster Field Office (Pasadena)
        Major utilities' EOC's including GTE, Pacific Bell, Southern
                California Edison
        City/County EOC's - Los Angeles City; Los Angeles County; Orange
                County; San Bernardino County; San Diego County; Santa
                Barbara County Operational Area
        American Red Cross National Operations Center, State EOC, 3 zone
                EOC's

13.     Response actions taken and resources committed by function

        Medical - California National Guard dispatching 10 air ambulances;
expected to arrive at 1/17/94, 1700 hours.  Urban search and rescue teams
and equipment being transported to Los Alamitos.

        Fire & Rescue - Orange County reports sending strike teams to L.A.
County.
        L.A. City reports major fire at San Fernando Road Trailer Park.
Natural gas fires in Balboa region.
        OES Fire & Rescue reports 30 strike teams ordered from Region VI
and 8 strike teams from the north state.

        7 of 8 of the state USAR teams have been activated. The eighth is
the City of LA which is committed to its own operations.  LA, Orange, and
Riverside county teams have been committed to assist LA City.  The others
will be stationed at Los Al; three northern CA teams on way from Travis AFB
1/17/94, afternoon. LA City being assisted by local USAR resources.  10
person federal USAR team enroute.

        Law Enforcement - LAPD and LASO are on tactical alert.  No requests
for out of area mutual aid.  Anticipate security problems with businesses.

        Transportation - Caltrans conducting damage assessment.  Receiving
calls from vendors offering equipment; so far Caltrans does not need extra
equipment.  Caltrans is coordinating resources from their unimpacted
districts; staff and equipment on standby.

        CHP reports 108 officers deployed in LA area; more call-ups
occurring.  They are on tactical alert.

        Water - DWR inspecting dams in area; dispatching two teams.  Dam
owners report no problems.  Owner of Santa Felicia Dam reports no damage.

        CCC - Assembling resources list

        Federal - Air Force will fly U-2 mission; photos will be ready by
2400 hours, 1/17/94; will have staff to interpret.


EDIS-01-17-94 1309 PST

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

Date: Mon, 17 Jan 1994 11:03:22 -0500
From: [e-mail] (Nigel Allen)
Subject: Los Angeles Earthquake, January 17
Organization: The National Capital FreeNet, Ottawa
Reply-To: [e-mail]


Information on the Los Angeles earthquake is available
in the ca.earthquakes newsgroup.


Nigel Allen      [e-mail]

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

Date: Mon, 17 Jan 94 06:37 PST
From: [e-mail] (Robert L. McMillin)
Subject: More on the LA Earthquake


At about 4:35 AM, Los Angeles suffered an earthquake of magnitude 6.6
on the Richter scale, centered in the San Fernando Valley.  Phones and
electricity were reported out throughout the entire Valley.  Major
fires started by gas main ruptures have been reported, and at least
four large apartment complexes have burned completely to the ground.

Valley residents will probably report this with more harrowing detail
that I can.

Los Angeles Mayor Richard Riordan announced one death on the freeways
caused by today's earthquake, but failed to say where or which
freeway.  Interstate 405, the main coastal artery, has suffered
extensive damage in the Valley, and is completely closed.  In fact,
except for one, all freeways in the San Fernando Valley are closed.
Los Angeles International Airport is closed.

Details as they come in.


Robert L. McMillin  | [e-mail] | Netcom: [e-mail]

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

From: [e-mail] (Dan Arthur)
Subject: FYI AT&T Reduces LA Quake Services to 203, 310, 805 and 818
Date: 17 Jan 1994 14:35:07 -0600
Organization: I-Link, Ltd., Des Moines, Iowa, US - 515/255-2754


FYI - from [e-mail]

The following area codes are considered in an emergency condition
according to a national newscaster:

    213 - California, Los Angeles
    310 - California, Beverly Hills
    805 - California, Bakersfield
    818 - California, Glendale

AT&T has apparently reprogrammed the long distance switching network
to free up lines for disaster personnel.  Any business with one of the
above area codes as an origin will likely have problems getting in
touch with you or vice versa.

Please e-mail any other specifics.

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

Date: Mon, 17 Jan 94 18:44 PST
From: [e-mail] (Lauren Weinstein)
Subject: Still Alive


Still alive.  A total mess, but still here.  Power just came back and
I just managed to bring up the main systems.  Miraculously, the routes
back to the net are up.  More details later.

Basically, much of the region is still w/o power and water.  I have
water in theory, but the main broke so I can't get at it.  The valley
is still largely black -- I'm amazed this area came back online as
soon as it did.  Phones stayed up pretty much throughout, with only
the usual overloading problems.

Definitely the worst I've been through in my lifetime here.  Much
worse damage than '71.


 --Lauren--


[TELECOM Digest Editor's Note: Please keep us posted whenever you can
with more details.  PAT]

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

Date: Mon, 17 Jan 1994 21:18:33 MDT
From: Rob Slade <[e-mail]>
Subject: Book Review: "Basics Book of Frame Relay" by Motorola


BKBSFRRL.RVW  931125

Addison-Wesley Publishing Co.
Kelly Ford, Promotion/Publicity Coordinator
P.O. Box 520    26 Prince Andrew Place
Don Mills, Ontario  M3C 2T8
416-447-5101  fax: [phone]
or
Tiffany Moore, Publicity  [e-mail]
John Wait, Editor, Corporate and Professional Publishing [e-mail]
1 Jacob Way
Reading, MA   01867-9984
800-822-6339  617-944-3700
Fax: [phone]
5851 Guion Road
Indianapolis, IN   46254
800-447-2226
"The Basics Book of Frame Relay", 0-201-56377-0

The preface states that this is an easy-to-read introduction to frame
relay for busy communications professionals who presumably want to
know something about the new technology besides the fact that it is
generating a lot of interest.  Fine.  I fit the bill perfectly.  I'm a
communications (specifically *data* communications) professional.  I'm
busy.  Let's get to the frame relay.

Not so fast.  First, we have an introduction that wants to tell me I
should be interested in frame relay.  Look, I got the book, didn't I?
Then, we have a chapter one which wants to tell me what a "protocol"
is, and about packet switching.  Pack it in, guys: I'm a professional,
remember?  Then, we get another *two* chapters of sales pitches!

Buried in the verbiage, there is a *bit* of information about frame relay:

-   it has higher throughput than X.25 (how?  less error correction and
    recovery);
-   you can connect anything to it (how?  probably the same way you do now--
    with difficulty);
-   you can connect voice to it (maybe.  or maybe that's *cell* relay, or ATM);
-   it has faster response time (how?  don't know);
-   it has higher throughput, again (how?  by letting you use more bandwidth,
    if it is available.  Huh.)

On the other hand, it takes less than an hour to read.


copyright Robert M. Slade, 1993   BKBSFRRL.RVW  931125
Permission granted to distribute with unedited copies of the TELECOM
Digest and associated mailing lists/newsgroups.

======================
DECUS Canada Communications, Desktop, Education and Security group newsletters
Editor and/or reviewer [e-mail], [e-mail], Rob Slade at 1:153/733
DECUS Symposium '94, Vancouver, BC, Mar 1-3, 1994, contact: [e-mail]

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

From: [e-mail] (Alfredo E. Cotroneo)
Subject: DBS Satellite Services in Europe
Date: 17 Jan 1994 04:53:32 -0600
Organization: UTexas Mail-to-News Gateway


I am looking for information on companies which offers audio subcarriers
on European DBS (Direct Broadcasts Satellite) such as the Astra(s),
the Eutelsat(s), Intelsat(s) or others.

As I have heard, tipically, unused audio subcarriers may be rented
directly also from companies which have rented a transponder, and use
it for their DBS TV transmission (e.g. MTV, Sky, TNT, etc.).

Phone and fax numbers of TV stations on European satellites, as well
as those of the original satellite service providers (AStra, Eutelsat,
etc. ) will be greatly appreciated.


Thanks,

Alfredo Cotroneo, Milano, Italy
[e-mail]
fax: [phone]

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

Date: Mon, 17 Jan 94 14:51 EST
From: [e-mail] (David L Kindred )
Subject: Case History of a Phone Rip-Off (Part 1)


As "Dragnet" used to say, "The following is a true story.  Only the
names were changed to protect the innocent".

My mother is Manager of a credit union in one of the small cities
adjacent to Newark, NJ.  The office is on the ground floor in a mixed
use area (street level business, upper floor residences). In addition
to herself, there are two part time employees.  They have two or three
phone lines coming in.  The local phone company is NJ Bell, and AT&T
is their long distance carrier.

One day, a NJ Bell service guy showed up.  After checking with her
employees, my mother informed him that no one had called for service,
and that everything thing was ok.  In a later conversation with her
computer service company, it turns out that they had called NJ Bell,
as they had had difficulty reaching my mother's office one day after
hours.  The computer service claims to have gotten some sort of
circuit failure intercept.

A day or two later, my mother was working late (there's a lot of extra
work this month generating 1099 forms and such).  At one point, my
mother picks up the phone to make a call, and finds a conversation in
progress.  Her first reaction was to hang up.  After thinking about it
for a minute, she realized that she was the only person in the office,
and that the lines couldn't be in use.  At this point she picks up the
line, and "This is the Credit Union, may I help you?".  One of the
people on the line mumbles something like "isn't so-and-so there?" and
hangs up.  My mother then hung-up and was able to use the line to make
her call.  The next day, she reported this event to NJ Bell.  A day or
two after that, one of the phone lines went dead, and again NJ Bell
was involved.

As you might expect, the next phone bill was quadruple the normal.
Most of the "mystery" calls were to Manilla (sp?), and a few to
Panama.

This is where things stand for the moment.  I'll report further on
whether NJ Bell/AT&T give her a hassle about the bogus charges, and
how long it takes to clear the "unexpected" connections.

This is the second time the credit union has been targeted for phone
rip-off.  The earlier incident involved improper third-party billing.
(Even though NJ Bell claims to only allow third-party billing after
voice confirmation, the bogus calls still occurred).  In that
incident, NJ Bell added third-party blocking to the Credit Union's
lines, and both NJ Bell and AT&T removed the bogus charges without
question.

Retribution may harsh if the parties involved are identified, as the
name of the credit union is "The xxxxxx Police and Firemen's Federal
Credit Union".  I think if I lived in a city, that would be the group
of people I'd pick on ...

There have been numerous reports here about unscrupulous persons
making their own connections to other people's phone lines.  The
person (or persons) involved here seem to have known that the lines
they "borrowed" were from a business, and what the normal working
hours for the business were.  Only a few late nights led to the
discovery of the problem before the first bill showed up.  Is there a
way a small business can protect themselves from this, or do we all
have to rely on the phone company straightening things out afterwards?


Dave

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

From: [e-mail] (Charles M Hatcher)
Subject: Cost of GTE Dialup Lines
Organization: The World Public Access UNIX, Brookline, MA
Date: Mon, 17 Jan 1994 19:56:00 GMT


I'm installing some dialup lines for a modem pool in an area served by
GTE South and I'm trying to figure out the most cost effective way to
order the lines.

A normal business line in this area costs about $52 per month flat
rate.  GTE doesn't offer measured use lines here.  In addition, to set
the lines up on a rotary will be $21 per month per line extra.  As far
as I have been to determine, in talking to GTE and looking through
their tariffs (which I admittedly don't have a complete grasp of)
there doesn't seem to be a cheaper way to go.  If I install 96 lines,
the cost will be about $7000 per month plus tax.

My question is this: Am I missing something here?  Is there a way to
get lines at a lower rate?  The lines need only be inward-dialing (no
calls will be made from them) and I don't need any PBX-type features.
All I need is a group of lines that can answer a single dialed number.
I'm willing to take individual lines or T1 multiplexed lines.  Anyone
have any experience with GTE's tariffs?  Thanks in advance!


Chuck Hatcher, Infomedia Corp.  [e-mail]

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

Date: Tue, 18 Jan 1994 08:52:28 NZS
From: Arnim Littek <[e-mail]>
Organization: Digi-Tech Ltd, Wellington, New Zealand
Subject: Shannon and Echo Canceller Protocols


>> But now I remember Shannon's Law (you have placed wrong the brackets):

>>      BPS(max) = Bw * log(2)(1+(S/N))

> I'm the one who originally posted this question, for those who don't
> know. It's nice to know what Shannon's law says -- if you assume a 30
> dB SNR and 3100 Hz bandwidth, the law above works out to about 31
> kilobits per second. If you happened to get a quiet channel, say, 40
> dB SNR, the equation returns about 41.2 kilobits per second. However,
> this is still quite a ways off from a full-duplex, 28.8 kbps link, or
> 57.6 kbps total transfer rate. So my question still stands: How do
> they do it? Are they assuming a particularly quiet channel? Are they
> assuming more than the standard 3100 Hz of bandwidth is available?

You've got most of it, now it just remains to understand how the
concept of echo cancellation fits into the picture.

While the actual telephone line sees both signals at the same time,
at each end, the receiver does not.  The echo canceller makes an
effort to remove most of the signal that had been transmitted (by
prior knowledge of the transmitted signal and the reflection
characteristics of the line it sees).

Hence the receiver at either end sees the S/N from the other end plus
the remaining noise from the incomplete cancellation of the
transmitted signal.  There is also a related effect from any hybrid
circuitry in the box, but not to the same degree.

I'm not trying to mathematically rigorous, but intuitively it has to
be close to this ...


Arnim      [e-mail]

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

From: [e-mail] (Michael Duane)
Subject: More on Communication Over Power Lines
Date: 18 Jan 1994 02:01:27 GMT
Organization: SEMATECH, Austin
Reply-To: [e-mail]


Thanks for the responses so far.  There are still some coming in, and
I need time to compile them.  When I can I will send you the
summarized results--they are interesting.

In the meantime, some food for thought:

Keep in mind that I was asking about long distance.  That is, it's
interesting to know that you can use the power lines to connect your
speakers (and how do they *do* that?), but how far can you go outside
of the house?

The transformers seem to pose a problem because of the high
inductance.  Agree or disagree?  Or is it because the signal would
have to be kilovolts on the line to make any detectable signal in the
home?  Or another reason?

Are the power lines tuned to 60 Hz to eliminate high frequency noise
and low frequency drift?  I've seen massive capacitors in the
substations, but I don't know what they do.  If the lines are tuned,
that would exclude telecom.

Still looking for that bandwidth vs. distance curve.  Can you use the
same curve as twisted pair?  I think not, because of skin resistance
in the power line, single wire approximations, etc.  However, some of
these considerations may not apply to the high frequency signal.

Related to the above, we know that the high frequency signal is
superposed on the larger amplitude 60 Hz.  However, in the
transmission line, maybe they follow different paths -- can this be?
Is the current path frequency dependent?

Thanks for the help!!

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

From: [e-mail] (Ross Porter)
Subject: V.32vis -> Bell_102 Due to CO Data Compression
Date: 17 Jan 1994 22:14:53 GMT
Organization: University of Pennsylvania, Department of Psychology


A few days ago my father-in-law reported that he could no longer get a
V.32bis connection between his Gainesville home and the University of
Florida's modem pool.  1200bps (Bell 102) was the best he could do.
He of course initially suspected his own equipment, but he later
learned from the data center staff that a number of other people
suddenly developed this problem.  The local telephone people reported
that they had recently installed some data compression equipment that
could well cause this problem.  Since voice traffic is relatively
unaffected, the phone company politely abdicated any further
responsibility.

Could someone speculate and enlighten me as to what kind of data
compression is being used -- is it lossy (given the large drop in
maximum transmission rate)?  I am not unsympathetic to the telephone
company's position, but does anyone have suggestions for lobbying the
telephone company?


Thanks,

Ross Porter    ross@psych

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

End of TELECOM Digest V14 #38
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