The Risks Digest

The RISKS Digest

Forum on Risks to the Public in Computers and Related Systems

ACM Committee on Computers and Public Policy, Peter G. Neumann, moderator

Volume 13 Issue 70

Thursday 6 August 1992


o Software problems plague new Canadian air traffic control system
Mark Bartelt
o Fun with high pressure
Michael Stern
o Mr. C. Baggage, who was neither a Mister nor a Baggage at all
Geoff Kuenning
o Unreliable call-return phone feature...
Rex Black
o GTE's Personal Secretary
Chuck Ham
o Police files
Nigel Allen
o Re: User interface studies: oh, what's the use?
Steve Summit
o Sweet Old Things and User Interfaces
Ed Ravin
o Re: Computer scoring glitch at Olympics
Stanley Chow
Joe Konstan
David Wittenberg
o 1993 Symposium on Research in Security and Privacy
Dick Kemmerer
o Info on RISKS (comp.risks)

Software problems plague new Canadian air traffic control system

Mark Bartelt <>
Tue, 4 Aug 92 06:49:37 EDT
        Glitches stalling updated airport radar
            Bugs mar new air control system
              Toronto Star, 3 August 1992
                 By Bruce Campion-Smith

   An $810 million program to install updated radar systems at Canada's major
airports has been stalled by a series of stubborn software bugs.  The
sophisticated system has crashed in tests and in actual use, freezing radar
screens, displaying false information and even showing jets flying backwards,
sources say.  In at least one case, air traffic controllers in Montreal were
left without radar for 15 minutes when the system suffered a "catastrophic
failure," according to federal documents.
   Controllers restricted flights and later that March night resorted to the
old radar system, according to a memo obtained by The Star under the Access to
Information Act.  At no time were passengers at risk, says a letter
accompanying the memo.
   "It's incredible.  It's a multi-million-dollar operation.  We're up to
version four and it's still not operational," said Paul Gauthier.  Gauthier is
vice-president, technical, with the Canadian Air Traffic Control Association,
the union representing the country's controllers.  "Government seems to be able
to get themselves in the situation where they are paying through the nose and
not getting the goods," he said.
   The system has been in use at Calgary International Airport since June 6 and
so far the system is working well, said Roger Westmore, Transport Canada's
project manager.  "There is a back-up, but we think it's unlikely it would be
required," Westmore said.
   That back-up is provided by controllers in Edmonton, and a switchover in the
event of a major failure of the system would take five to 10 minutes, Gauthier
said.  "I couldn't believe it, but that's what they are doing," he said.  "It's
not certified or commissioned, but they are running live tests with live
people."  The massive program is known as the radar modernization project
(RAMP) and is touted as one answer to easing congestion -- and reducing delays
-- in the skies above congested airports, like Person International.
   The new radar replaces vacuum-tube technology with a better picture of
what's happening in the skies.  That would allow them to space aircraft closer
together and, in the end, get more flights in and out of busy Pearson.
   Transport Canada officials say they are close to clearing "the last hurdle"
and are optimistic that the system will be up and running at Pearson early next
year -- 2 1/2 years after originally expected.  The system should be fully
operational across Canada within the next six months, Westmore said.  But
controllers and airline representatives are less hopeful.  "That's the story
we've been getting for the last three years.  It's always just around the
corner," said John Redmond, president of the controllers' association.
   "It's crashed in Montreal.  It's crashed in Moncton.  It's crashed in
Toronto," Redmond said.  "The problem is primarily with the software not being
able to handle the amount of data that runs through the system, and it keeps
crashing," Redmond said.
   Controllers who have experienced an unnerving system crash say they never
know how long they'll be without radar when it happens.  That's why the new
system is losing the trust of the very people who will have to use it, Gauthier
   The system screw-ups in testing include:
 -- Switching the data tags between two aircraft when the planes are close
together on the radar screen.  The tags are vital, identifying the green blips
on the screens.
 -- Backing up targets on the screen, in essence showing jets flying backwards.
   Developing a software package that would work in Toronto Centre -- the
busiest airspace in Canada -- has remained the big hurdle, sources say.  One
stumbling block has been the system's inability to handle heavy traffic.  Just
when designers think they have one glitch cured, another pops up, sources say.
The curious problems struck as recently as last month, when the latest package
of software was tested in Moncton and failed, they say.
   Westmore denies the system failed and instead says it needed "additional
improvements."  With a project of this magnitude, it's normal to expect some
problems, he said.  The contract for the system was awarded to Raytheon Canada
Ltd. in 1985.

Fun with high pressure

Michael Stern <>
4 Aug 92 03:43:17 GMT
Beware of high pressure without passive safety devices!  The following account
of a near accident at a research university is constructed from conversations
with a friend of mine who will remain nameless, as will his university.

Researchers were attempting to measure directly the permeability for melt
transport through a matrix of partially molten rocks. This required the use
of a digitally controlled high-pressure pump (a 25,000 psi Single-Cylinder
Positive Displacement Pump manufactured by Ruska Instruments of Houston, TX.)

The pump was controlled by a ZEOS 386 clone via a serial line. On the day in
question, the computer froze while the pump was compressing the system at full
speed. Before dying, it sent enough garbage across the serial line to confuse
the pump's keyboard, so that researchers lost all software control of the pump,
which merrily continued to compress past the software pressure limit which had
been set (corresponding to the maximum pressure for the tranducers in the
system, 2000 psi). It got to 4000 psi, the threshold for permanent damage to
the transducers, before they managed to switch the power to the pump's motor
off. This is particularly scary because the pump will go to 25,000 psi, but the
plumbing was rated only for 20,000 psi so it would probably have been an
explosive failure.

They had had problems with the clone in the past; most of which were believed
related to the Extended Memory Manager.

It should be noted that the following safety precautions would eliminate this
type of danger: use of _hardware_ travel limit switch as well as software
pressure limit. Also, any system with pressure-sensitive parts should always
have at least one safety head equipped with a suitable rupture disk.

Michael Stern

Mr. C. Baggage, who was neither a Mister nor a Baggage at all

Geoff Kuenning <desint!geoff@uunet.UU.NET>
Tue, 4 Aug 92 23:43:36 PDT
Some years ago, a cellist acquaintance landed a job on the opposite coast.
Like all serious cellists, she bought a second ticket for her valuable
instrument rather than subject it to the vagaries of airline baggage handling.

As it happened, someone near the destination later offered her the use of
another fine cello so that she wouldn't have to bring her own.  Stuck with an
extra ticket, she successfully advertised it for sale.  The only catch was that
the purchaser had to identify himself as Mr. C. (for Cabin) Baggage when he
boarded the flight.

It seems that the ticket-reservation system doesn't have a provision for
tickets issued to non-persons.  A blank field is an error, and there is no
override.  I've heard of some pretty creative names invented by cellists to
identify their instruments on flights.

    Geoff Kuenning   uunet!desint!geoff

            [She could buy a ticket for the 'cello case in the name
            of Justin Case -- just in case she needed the extra seat.
            Further confusions arise ticketing a baseball pitcher named Viola
            or someone associated with ClariNet.  (Playing first bass/base
            is clearly ambiguous orally/aurally/AuraLee.)  There are also
            rigorous orchestras with Horn Clauses in their contracts.  PGN]

Unreliable call-return phone feature...

Rex Black <>
Tue, 4 Aug 92 09:33:02 CDT
I know that caller ID has generated a number of discussions about privacy and
risks to individuals.  I'd like to pass on a personal experience I had with a
related technology, call return.

I was using my modem and computer to telecommute on Sunday afternoon.  Shortly
after hanging up, my phone rang.  The caller asked with whom she was speaking.
I responded by asking who she was trying to reach.  It turned out that she had
just been the victim of a harassing phone call.  Southwestern Bell has a phone
feature (call return) that allows a person to press a star-sequence (i.e., *1)
to call back the last caller.  According to the phone salesman who
(aggressively) marketted it to me when I had my phone connected three months
ago, it uses the same logic as caller ID.  (He mentioned that Southwest Bell
would offer caller ID in the fall.)  He promoted call return as a "great way to
deal with obscene or harassing callers."  My experience Sunday afternoon points
out a serious risk associated with such technology.  Clearly, the system has a
bug.  That bug lead someone to believe that I was harassing them.  Depending on
what was said, the system identified me as a misdemeanant or a felon.

On Monday, I called Southwestern Bell and explained my concern.  While the
person I spoke with understood my concern, he did not help.  He repeated the
standard disclaimer about "no phone system is perfect, the phone company can
not guarantee accuracy, blah, blah, CYA, CSWBA..."  I did manage to get from
him some further information: First, this was hardly the first time this
happened.  He mentioned that incidents like mine occur frequently.  Second, the
phone company's policy requires that, before turning a case over to the police,
someone must repeatedly call and harass someone.  One instance does not

I then called the P.U.C.  I spoke with a woman there who, when she realized I
was calling to voice concerns about caller ID and call return, adopted a very
tired tone of voice.  She gave me a docket number and said that I should send
in my comments to the P.U.C.  I asked about groups who may have joined fight
against such technology.  She said that SWB had just submitted the caller ID
request, but she expected that a number of people would get involved in the
ensuing discussion.  She did not sound pleased at the prospect.

GTE's Personal Secretary

Chuck Ham <>
Tue, 04 Aug 92 08:20:27 EDT
General Telephone is just now offering the "Personal Secretary" voice message
service to the public here.  In recent newspaper ads GTE touts that the service
takes messages, reminds you of important dates, has a wake up service, and can
be programmed up to a year in advance.  Sounds like I can throw away my answer-
ing machine, my date book, my alarm clock and my computer, all for the low
price of $5.95 a month with the first 30 days free!

Customers, however, are not made aware of some of the risks involved.  A friend
was recently made a victim of the service WITHOUT subscribing.

She noticed her home phone (which she always used to receive client calls) was
not ringing and no messages were being left on her answering machine.  Several
times when she tried to dial out a strange tone came over the receiver.  This
went on for several days until her business associate complained of the same

After discussing this with GTE my friend discovered that a church-friend that
works for GTE signed up SEVERAL people without their knowledge.  (She thought
it was a "nice" thing to do.)

My friends problems with the "Personal Secretary" were caused by the way the
system is set up.  First, it answers on the first ring, therefore it wouldn't
activate the answering machine or allow a person to answer.  Second, without
the proper code number you cannot retrieve your messages (the tone she heard
was alerting her to the messages she had waiting... but of course she had no
idea what it was for).  Needless to say my friend was not impressed!

How could the phone company employee sign someone up without their knowledge or
signature?  Doesn't GTE have some legal obligation to notify a customer before
tapping a service onto their line?  Can they just do it without any proper

Chuck Ham  Radio/TV Information Specialist
University of Kentucky

Police files

Nigel Allen <>
Fri, 31 Jul 1992 20:00:00 -0400
 New York Awarded Funds to Improve Criminal History Records
 To: State and City Desks
 Contact: Stu Smith of the Office of Justice Programs,
          U.S. Department of Justice, 202-307-0784 or
          301-983-9354 (after hours)

   WASHINGTON, July 30 /U.S. Newswire/ -- The U.S. Department of Justice has
awarded the state of New York $381,512 to continue its program of improving the
quality of the state's criminal history recordkeeping, the Bureau of Justice
Statistics (BJS) announced today.  The project, administered by BJS in the
Office of Justice Programs (OJP), is part of a three-year, $27 million program
established by the Attorney General to help states upgrade current systems used
to maintain records of arrests, prosecutions, convictions and sentences.  The
Bureau of Justice Assistance is providing the funding through the Edward Byrne
Memorial State and Local Law Enforcement Assistance Program.
   "The major objective of this cooperative agreement is to improve the overall
quality of the state's criminal history record information by improving
disposition reporting, " said BJS Director Steven D. Dillingham.  "This
administration is making every effort to assure the highest standards of
accuracy and timeliness in criminal history record information across the
country.  It is critical that law enforcement officers, prosecutors, judges and
corrections officials have access to complete and accurate information on each
individual within the purview of the criminal justice system," Dillingham
   The New York Division of Criminal Justice Services will use the assistance
to correct database problems identified during the first phase of the program
and complete a study to determine if problems related to disposition collection
can be systematically resolved.  "The program emphasizes the recording of
arrest, conviction and sentencing information in a form that will make felony
history information more reliable and complete," Dillingham commented.  "This
is a crucial component of the overall objective of insuring that state criminal
history records are up-to-date and available to all criminal justice agencies."
Additional information about this program is available from BJS.  Publications
and statistical and research data may be obtained from the National Criminal
Justice Reference Service, Box 6000, Rockville, Md. 20850.  The telephone
number is 301-251-5500.  The toll-free number is 800-732-3277.

Canada Remote Systems  - Toronto, Ontario/Detroit, MI
World's Largest PCBOARD System - 416-629-7000/629-7044

Re: User interface studies: oh, what's the use? (Slade, RISKS-13.69)

Steve Summit <>
Tue, 4 Aug 92 15:09:55 -0400
Robert Slade writes:
> Couple... at next ticket machine looking very
> worried...: "How do you work this?"  Point out large legend at top...  Point
> out large A by map, B by buttons, etc.  Couple goes back to worrying in
> front of next ticket machine.

There's a fundamental problem here which we might as well lump together with
computer literacy (or lack thereof).  Many people have an instinctive,
gut-level response to anything that "looks technical": "Oh, this is too
complicated.  I can never figure these things out."  No amount of (impersonal)
hand-holding in the form of allegedly idiot-proof instruction will help; these
people's minds are firmly made up.  ("The lady doth protest too much, methinks"
applies -- if a technical system, for use by the masses, seems to need
"idiot-proof" instructions, it's probably too late.  Don Norman's POET
discusses this phenomenon well, and at length.)

The instinctive response ("I can't figure this out") is irrational, because
there are many allegedly idiot-proof technical systems out there which are
truly inspired in the techniques they employ to achieve alleged
idiot-proofness, techniques which render the interfaces accessible to just
about anyone *if they try*.  But remember, humans are basically irrational
creatures (which only makes irrational responses harder to understand for those
of us who occasionally try to be rational).

A lode that newspaper columnists have been gleefully mining lately is disgust
(theirs and their readers') over voice mail systems ("push 1 if you would like
to...").  These systems, when implemented well, can be much more efficient than
waiting on infinite hold for harried, human operators.  But the people doing
the complaining want to talk to a person, they don't want to push buttons.

I think it will take a couple of generations before there is any kind of
widespread approval and appreciation of these and other similarly technical
                    Steve Summit

Sweet Old Things and User Interfaces (Slade, Re: RISKS-13.69)

Unix Guru-in-Training <elr%trintex@uunet.UU.NET>
Tue, 4 Aug 1992 14:42:13 GMT
Robert Slade, in RISKS 13.69, describes the scene in front of various
automatic teller machines and ticket machines and sees that in spite
of clear and instructive diagrams (to him) people (especially older
people) are still having trouble using automatic machines.

Although it's a little hard to read Robert's prose, he appears to be saying
that no matter how smart the computer is, some people are still too stupid to
use it.  I'm a bit worried by that -- the readers of RISKS are all fairly
sophisticated computer users who can handle the various commands of Unix, VMS
and fourteen million different mail-readers.  Have we forgotten that not
everyone else in the world uses computers the way we do?  That operating a
machine, be it a soda vending machine, vacuum cleaner, bank machine, or Sun
workstation, is not a skill human beings are born with?

If the user interface is too difficult for most users to figure out, it's not
the user's fault.  It may not even be the machine's fault -- it may just be the
job the machine is trying to do is too complicated for the average person.  The
problem is that is was designed by "computer geeks" like us, who don't have a
problem learning a difficult interface.

Perhaps as the older generation passes, replaced by a generation born using
Nintendos, remote controls, digital watches, and other accoutrements of the
digitized era, the minimum ability of the average person to use a machine
interface will increase.  But until then, we shouldn't fall into the trap of
blaming the victim for the inadequate user interface.

Ed Ravin   elr@trintex.uucp    +1-914-993-4737

re: Computer scoring glitch at Olympics (Carr, RISKS-13.69)

Stanley (S.T.H.) Chow <SCHOW@BNR.CA>
4 Aug 92 10:07:00 EDT
This is a good illustration of a problem that is often blamed on copmuter
systems, particularly when cutting in a new system.

   People forget that it is a different game.

The rules were changed (I presume at the insistance of the Americans as a
result of the Soul Olympics), why should one expect the same result from the
new rules as the old obsolete rules? The fact that a computer system was used
to keep score under the new rules is neither here nor there (unless there has
been a real computer glitch).

One can conjure up many different possible reaons why the new rules give a
result different from the old rules, one can also argue endlessly as to which
set of rules are better, but rules are rules.

To bring this back to RISKS: using a new computer system to implement a new set
of rules can bring about surprising result, having people in the loop adds a
degree of self-correction.

Stanley Chow        (613) 763-2831

BNR, PO Box 3511 Stn C, Ottawa, Ontario, Canada K1Y 4H7 BitNet: schow@BNR.CA  ..!uunet!bnrgate!bcarh185!schow

Re: Computer scoring glitch at Olympics

Joe Konstan <>
Mon, 3 Aug 92 19:02:55 PDT
In RISKS-13.69, John Carr presents a _Boston Globe_ except about a "computer
glitch" that eliminated US boxer Eric Griffin.  As someone who watched the
fight (tape delayed) on TV, and has been following the controversy, I'd like to
add a few points that are missing from the article.

There are two main human reasons why the computer system, which most
commentators thought functioned properly, would record such a score.  First is
the "Nintendo effect"--boxing judges don't tend to have particularly good
reaction times, and therefore may miss the one-second cutoff.  Second is a
particularly bad judge, who recorded only 13 punches total while the others
averaged 29.5.  This judge had just returned from a two day suspension for poor

To understand the system, it is somewhat useful to understand the layout of the
ring judges.  This picture is approximate:

           |        |
        X  |        |  X
           |        |
             X   X

Under the new scoring system, the main score is based on a majority of judges
recognizing any punch.  Since at least one, and often two will have obscured
views, a single bad judge really can throw off the system WITHOUT ANY COMPUTER

Finally, this particular match, while extremely shocking, is not that unusual.
Throughout these olympics, a large number of clear punches, particularly to the
body, have not been scored.

As we see again and again, a computer cannot take a poor system and make it
better--but it can provide a focus for blame.
                                                        Joe Konstan

Re: computer scoring at olympics (RISKS-13.69)

David Wittenberg <>
Wed, 5 Aug 92 19:08:41 -0700
If you don't know how to do something, you don't know how to do it with a

  The real problem is that boxing has not decided what they mean by "landing a
blow".  Note that the individual scores vary by more than a factor of 3.  If
the judges differ by a factor of three, how can they expect that software will
mediate this difference?  I suspect that the software did exactly what it was
specified to do.

According to the commemtators, the new scoring system has changed the
style of boxing.  Computers cannot decide what the rules should be, but
they can, and perhaps should, be used to see what results different rules
give, and one can they chose the rule that most closely correlates with
the judges' impressions.

--David Wittenberg

1993 Symposium on Research in Security and Privacy

Thu, 06 Aug 92 15:05:45 PDT
                   CALL FOR PAPERS
              1993 IEEE Symposium on Research in Security and Privacy
                      Oakland, California, May 24-26, 1993

                    sponsored by
                    IEEE Computer Society
              Technical Committee on Security and Privacy
                     in cooperation with
    The International Association for Cryptologic Research (IACR)

The purpose of this symposium is to bring together researchers and developers
who work on secure computer systems.  The symposium will address advances in
the theory, design, implementation, evaluation, and application of secure
computer systems.  Papers and panel session proposals are solicited in the
following areas:

    Secure Systems      Privacy Issues      Information Flow
    Network Security    Formal Models       Viruses and Worms
    Database Security   Access Controls     Security Verification
    Authentication      Data Integrity      Auditing and
                               Intrusion Detection


Send six copies of your paper and/or panel session proposal to Richard Kemmerer,
Program Co-Chair, at the address given below.  Put  names and affiliations of
authors on a separate cover page only, as a ``blind'' refereeing process is
used.  Abstracts, electronic submissions, late submissions, and papers that
cannot be published in the proceedings will not be accepted.

Papers must be received by November 15, 1992 and must not exceed 7500 words;
papers that exceed this length will be rejected without review.  Authors will
be required to certify prior to December 25, 1992 that any and all necessary
clearances for publication have been obtained.  Authors will be notified of
acceptance by February 1, 1993.  Camera-ready copies are due not later than
March 15, 1993.

The Symposium will also include informal poster sessions.  Send one copy of
your poster session paper to Teresa Lunt, at the address given below, by
January 31, 1993.  Electronic submission of the latex source for poster
session papers is strongly encouraged.  Poster session authors must send a
certification with their submittal that any and all necessary clearances for
publication have been obtained.

                 PROGRAM COMMITTEE
Tom Berson          Paul Karger         Jon Millen
  Anagram Laboratories        OSF             MITRE
Deborah Cooper          Tanya Korelsky      Jeff Picciotto
  Paramax Systems Corporation     ORA             MITRE
George Dinolt           Sue Landauer        Phillip Porras
  Loral Labs              TIS             Aerospace
Virgil Gligor           Teresa Lunt         Ravi Sandhu
  University of Maryland      SRI             George Mason Univ.
Deborah Hamilton        Doug McIlroy        Marv Schaefer
  Hewlett-Packard Laboratories    AT\&T Bell Labs     CTA
Jeremy Jacob            John McLean         Brian Snow
  Oxford University       NRL             NSA
Sushil Jajodia          Catherine Meadows   Yacov Yacobi
  George Mason University     NRL             Bellcore

For further information concerning the symposium, contact:

 Teresa Lunt, General Chair         Cristi E. Garvey, Vice Chair
 SRI International, EL245       TRW, MS R2-2104
 333 Ravenswood Avenue          One Space Park
 Menlo Park, CA 94025           Redondo Beach, CA 90278
 Tel: (415)859-6106             Tel: (310)812-0566
 FAX: (415)859-2844             FAX: (310)812-7147

 Richard Kemmerer, Program Co-Chair     John Rushby, Program Co-Chair
 Computer Science Department        SRI International, EL254
 University of California       333 Ravenswood Avenue
 Santa Barbara, CA 93106        Menlo Park, CA 94025
 Tel: (805)893-4232             Tel: (415)859-5456
 FAX: (805)893-8553             FAX: (415)859-2844 

        Jeremy Jacob, European Contact
        Oxford Univ. Computing Laboratory
        11 Keble Road
        Oxford, England OX1 3QD
        Tel: +44 865 272562
        FAX: +44 865 273839

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