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 12 Issue 64

Friday 15 November 1991


o MCI's Response for RISKS
Sally McCaffrey
o Computer-assisted trading
Brendan Kehoe
o Risks of truncation in the stock market
Frank G Kienast
o gray vs gorman
Fred Gilham
Peter G. Neumann
o 5th Refinement Workshop: Theory and Practice of Formal Software Development
Cliff B Jones
o Info on RISKS (comp.risks)

MCI's Response for RISKS

Thu, 14 Nov 91 22:20 GMT
                                MCI Telecommunications Corporation
                                Consumer Relations
                                Consumer Markets
                                1200 South Hayes Street
                                Arlington, Virginia  22202
                                (703) 425-6000

                                November 13, 1991

In response to the piece posted by Brian R. Krause on your [inter]national
bulletin board, RISKS Forum, titled "MCI Friends & Family & anyone else with a
touch-tone phone" on October 23, 1991, MCI wishes to post the following

MCI is aware and sensitive to privacy concerns of its Friends & Family

Additionally, MCI is aware of the isolated incident where its Friends & Family
voice response unit (VRU) Update Line was abused.  MCI has made -- effective
November 7 -- the access more private by altering the VRU access procedures.

In order to acquire information about a Friends & Family Calling Circle,
customers have two options depending on the information they want.

        Option 1:  Enter the last three digits of your MCI account number to
        receive the status of all Calling Circle members.

        Option 2:  Enter an individual Circle member's 10-digit phone number
        to learn the status of that individual.

We hope this explanation addresses any concerns that may have arisen as a
result of the "RISKS" posting.

Karen Heyison, Manager, Consumer Relations

computer-assisted trading

Brendan Kehoe <>
Sat, 16 Nov 1991 12:49:28 -0500
 Yesterday's sudden fall in the stock market brought to light a serious
Achilles heel in the way our country's economy is growing.  As panic hit more
and more traders, the faint clatter of computer keyboards added to the fray --
virtual stocks were being virtually sold at an amazing pace.

 It was less of a concern in the 1989 crash, but now we should be even more
aware of the effect computer-assisted trading can have on the market.  Inside
of ten minutes, millions of shares can be unloaded very quietly.

 The securities industry can only grow faster in the coming years; if it
doesn't build some cushions to avoid massive "anonymous" selling, it may be in
for an even more serious down-turn.

Brendan Kehoe, Sun Network Manager, Widener University, Chester, PA

Risks of truncation in the stock market

Frank G Kienast <well!>
14 Nov 91 01:50:26 GMT
In their stock statistics sections, Prodigy has a 14-character maximum
length for the company name.  Apparently, they just chop off any remaining
characters.  This morning, I was surprised to see the following stock among
the ten listed under yesterdays "NYSE Biggest Percent Gainers":

STOCK           LAST            CHANGE          PCT CHG
ELECTRONIC ASS  2 3/8           + 1/4           11.76

(I think this is supposed to be Electronic Associates, ticker EA).

Well: well!fgk@ucbvax.Berkeley.EDU  CIS: 73327,3073 V-mail: 804-980-3733

gray vs. gorman (RISKS-12.61-63)

Fred Gilham <>
Fri, 15 Nov 91 06:39:40 -0800
I've completely lost track of what's going on with the gray vs. gorman
"discussion".  I hope you'll put something in the next Risks saying that
further communications on the issue will be conducted through the lawyers of
the parties involved or something to that effect, something that leaves RISKS
out of it!

P.S.  I'm sure this is an example of the risk of computer communication -- most
people would post things they wouldn't say to another person standing next to

gray vs. gorman (RISKS-12.61-63)

Peter G. Neumann <neumann@CSL.SRI.COM>
Sat, 16 Nov 91 14:14:26 PDT
I greatly appreciated all the supporting mail I received on this topic.  I try
very hard to keep RISKS consistent with the self-imposed standards of being
INFORMATIVE.  I certainly learned something from both antagonists, and about
them.  Whether or not that was RISKS-RELEVANT or not, I believe that once
something unfortunate has slipped through, it becomes necessary to set the
record straight.  But in keeping with the current efforts to raise the
standards (again) in the continuing epicyclicity of RISKS, there are likely to
be fewer mundanities for a while.  Thanks again to all of you for your
continuing contributions, including those that do NOT get included.  Sorry, I
cannot respond to everything.  So, if you think I missed a GOOD ONE, PLEASE
poke me; I probably did miss it, especially if the Subject: line was
nonspecific.  PGN]


Peter G. Neumann <neumann@CSL.SRI.COM>
Sat, 16 Nov 91 14:12:16 PDT
    [I will have very limited net access for the next few weeks, and would like
    to post one more reminder for SIGSOFT '91 before it happens.  Registration
    is coming along very nicely, and hotel space is starting to fill up, so
    those of you wishing to register might want to do so soon.  Please contact
    Judith Burgess for further details:
       Registration and Coordination:  Judith Burgess, SRI International phone: (415) 859-5924, FAX (415) 859-2844
    Thanks.  PGN]

                        4-6 December 1991
                    Fairmont Hotel, New Orleans


Welcome and Introduction: 8:45am - 9:00
  Mark Moriconi, SIGSOFT '91 Chair (SRI International)
  Peter G. Neumann, Program Co-chair (SRI International)

Session 1: 9:00 - 10:15, Carl Landwehr, Chair

  Formal Verification of Algorithms for Critical Systems
     John Rushby (SRI International), Friedrich von Henke (University of Ulm)

  State-Based Model Checking of Event-Driven System Requirements
     Joanne M. Atlee and John Gannon (University of Maryland)

  Open Discussion

Session 2: 10:45 - 12:30, Dines Bj/orner, Chair

  Rigorous Development Using RAISE
     Bent Dandanell (CRI, Birker/od, Denmark)

  Specifying and Verifying Requirements of Real-Time Systems
     K.M. Hansen, A.P. Ravn, and Hans Rischel (Tech. University of Denmark)

  A Systematic Kernel Development
     J.F. S/ogaard-Andersen, C.O. Rump and H.H. Lovengreen (Tech. Univ. Denmark)

  Open Discussion

Session 3: 2:00 - 3:45, John Rushby, Chair

  The Infeasibility of Experimental Quantification of Life-Critical
  Software Reliability
     Ricky Butler and George Finelli (NASA Langley Research Center)

  PANEL: The Limits of Probabilistic Risk Assessment

     Bev Littlewood (City University, London)
     David Parnas (McMaster University)
     Martyn Thomas (Praxis, Ltd)
     Ricky Butler (NASA Langley Research Center)
     John Musa (AT&T Bell Labs, Whippany, NJ)

    The Butler/Finelli paper argues that ultra-high reliability cannot be
    validated directly from testing, nor can be it demonstrated by appeals
    to software fault-tolerance.  What progress might we reasonably expect
    to make toward numerical risk assessment of life-critical software?

Session 4: 4:15 - 5:30, Martyn Thomas, Chair

   PANEL: The Confused World of Standards for Critical Software

   Martyn Thomas (Praxis, Ltd)
   Peter Neumann (SRI International)
   Mike DeWalt (FAA)

   This session will explain and assess current government regulation such as
   British MoD DEFence STANdard 00-55/56 and various security criteria (e.g.,
   U.S. TCSEC, European ITSEC, Canadian CTCPEC).  What role should such
   standards play?  What should be mandated?


Session 5: 9:00am - 10:30

  Comparing Fault Detecting Ability of Testing Methods
     P.G. Frankl (Polytechnic University), E.J. Weyuker (NYU Courant Institute)

  An Exception Handling Model For Parallel Programming and its Verification
     Valerie Issarny (IRISA/INRIA)

  Open Discussion

Session 6: 11:00 - 12:30

   INVITED TALK:  Human Error in Design
       Henry Petroski (Duke University)
         Author of the widely-acclaimed books ``To Engineer is Human: The
         Role of Failure in Successful Design'' and ``Pencil''

Session 7: 2:00 - 3:30, Victoria Stavridou, Chair

  A Real-Time Transition Model for Analyzing Behavioral Compatibility of
  Telecommunications Services
     E.J. Cameron and Y-J Lin (Bellcore)

  Programming and Verifying Critical Systems by Means of the Synchronous
  Data-Flow Language LUSTRE
     C. Ratel (Merlin-Gerin), N. Halbwachs and P. Raymond (IMAG/LGI)

  Open Discussion

Session 8: 3:45 - 5:30, Mark Moriconi, Chair

Invited Presentations on Practical Experiences:

  Validation of Critical Flight Controls
     Jim McWha (Chief Engineer in charge of 777 Flight Controls, Boeing)

  Reliable Software for the 4 ESS Switch
     Michael Meyers (AT&T Bell Labs)

  A Case Study of the THERAC-25 Accidents
     Nancy Leveson (U.C. Irvine)

Session 9: 8:00pm - 9:30pm, Evening Poster Session


Session 10: 8:30am - 10:30, Hermann Kopetz, Chair

  Stepwise Design of Real-Time Systems
     Reino Kurki-Suonio (University of Technology, Tampere)

  On Satisfying Timing Constraints in Hard-Real-Time Systems
     Jia Xu (York University) and David Parnas (McMaster University)

  Automated Analysis of Bounded Response Time for Two NASA Expert Systems
     C-K Wang, R-H Wang, D-C Tsou, J.C. Browne, and A.K. Mok (University
     of Texas, Austin)

  Open Discussion

Session 11: 11:00 - 12:30

PANEL: Future Directions, Nancy Leveson, Chair

Adjournment at 12:30

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AIR TRANSPORTATION.  Delta Airlines is offering 40% off RT Coach fares within
the U.S., 35% Canada, 5% off already discounted fares.  Call 1-800-221-1212,
ask for Special Meeting Network, refer to file ref no. V18006.  Valid for
travel from Nov. 30 to Dec. 10.  7-day advance purchase required.

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     SIGSOFT '91 -- Software for Critical Systems
    Fairmont Hotel, New Orleans, Dec. 4 -- 6, 1991

Name _________________________________________________________
Affiliation __________________________________________________
Address ______________________________________________________
City, State and Zip __________________________________________
Phone (and FAX) ______________________________________________
Email address ________________________________________________
ACM or SIGSOFT Membership No. ________________________________

Registration Fees

   ACM or SIGSOFT Member       $330
   Non-Member                  $380
   Full-time Student           $230

To pay by credit card, circle one:    AMEX        VISA       MC
Name on card __________________________________________________
Card number ___________________________Exp. date ______________
Signature _____________________________________________________

Make checks payable to SIGSOFT '91 in U.S. dollars.  Fees include 3 continental
breakfasts, 2 lunches, and the Proceedings.

Dietary requests:  Vegetarian ______  Kosher ________

Judith Burgess / EL266, SRI International, 333 Ravenswood Ave.,
Menlo Park, CA 94025, USA

For further information, contact Judith Burgess,
telephone: (415) 859-5924, FAX (415) 859-2844, EMail


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    SIGSOFT '91 -- Software for Critical Systems
          New Orleans, Dec. 4 -- 6, 1991

Name _________________________________________________________
Affiliation __________________________________________________
Address ______________________________________________________
City, State and Zip __________________________________________
Phone (and FAX) ______________________________________________
Date/Time of Arrival _________________________________________
Date/Time of Departure _______________________________________

Room Rates (subject to taxes):

Circle one:                Single $99         Double/Twin $119

RESERVATIONS: 1-800-527-4727 or 1-504-529-7111

To guarantee your reservation by credit card:

Circle one: AMEX     MC     Visa    Carte Blanche  Diners Club

Name on card _________________________________________________
Card number ___________________ Exp. date ____________________
Signature ____________________________________________________

These rates apply from Nov. 29 through Dec. 8, subject to availability.
Reservations should be received 30 days in advance to ensure availability, but
later reservations will be accepted as possible.  A deposit for the first night
must accompany your reservation to guarantee it for arrival after 6:00pm.
Cancellations must be made 24 hours in advance.

The Fairmont Hotel, University Place, New Orleans, LA 70140, USA
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   General Chair:  Mark Moriconi, SRI International
   Program Co-Chairs:  Peter Neumann, SRI International
                       Nancy Leveson, Univ. of California, Irvine
   Travel Arrangements:  Johnette Hassell, Tulane University
   Registration and Coordination:  Judith Burgess, SRI International
 phone: (415) 859-5924, FAX (415) 859-2844

   Program Committee:
       David Barstow       (Schlumberger)
       Dines Bj/orner      (Technical University of Denmark)
       Marie-Claude Gaudel (Universite de Paris - Sud)
       Jim Horning         (DEC Systems Research Center, Palo Alto)
       Bill Howden         (University of California, San Diego)
       Hermann Kopetz      (Technical University of Vienna)
       Carl Landwehr       (Naval Research Laboratory)
       Bev Littlewood      (City University, London)
       Leon Osterweil      (University of California, Irvine)
       David Parnas        (McMaster University, Canada)
       Fred Schneider      (Cornell University)
       Vicky Stavridou     (University of London)
       Martyn Thomas       (Praxis, Inc.)
       Walter Tichy        (University of Karlsruhe)
       Elaine Weyuker      (NYU Courant Institute)

5th Refinement Wkshp: Theory and Practice of Formal Software Develpmnt

Cliff B Jones <>
Fri, 15 Nov 91 16:35:15 GMT
                                BCS FACS
                       Fifth Refinement Workshop
           Theory and Practice of Formal Software Development
                         8 - 10th January 1992
                               LONDON, UK

     Sponsored by Lloyd's Register, Program Validation Ltd and the DTI

The workshop theme is Refinement: the systematic decomposition of formal
specifications into designs which are functionally correct or implement
important properties such as safety or information security.

VENUE: Lloyd's Register of Shipping, 71, Fenchurch Street, London EC3

INVITED SPEAKERS:    Roger Jones                  ICL
                     Prof. Robin Milner FRS       University of Edinburgh
                     Dr Jose Oliveira             University of Minho
                     Dr Jim Woodcock              University of Oxford

Registration fees include lunchs, intermission refreshments, workshop handouts,
full Proceedings published by Springer-Verlag (to be dispatched after the
workshop), and a social evening event.

Accommodation costs are not included in the registration fee, but rooms can be
booked in student accommodation at the City University which is a short
Underground ride or a two mile walk from the Workshop venue. The cost of
accommodation and breakfast at the City University is 17 pounds inclusive of

A limited number of assisted places are available at 60 pounds for bona fide
research students. To apply for this please use the registration form and do
not enclose the fee yet.

A 10 pound premium is charged for registration not accompanied by a fee, except
for those initially applying for an assisted place.

A Tools Exhibition will be held. Potential exhibitors please contact the
Publicity Officer.

ORGANISING and TECHNICAL COMMITTEE: Prof. Bernard Carre (Chairman), Prof.
Cliff Jones nslation(Technical Programme), Roger Shaw (Local Arrangements), Paul Smith
(Publicity), Dr. John Cooke, Tim Denvir, Jeremy Jacob.

CHAIRMAN:  Prof Bernard Carre          PUBLICITY: Paul Smith
           Program Validation Limited             Secure Information Systems Ltd
           26   Queen's Terrace                   Sentinel House
           Southampton                            Harvest Crescent
           SO1 1BQ                                Ancells Park
           Tel: +44 (0)703 330001                 Fleet
           Fax: +44 (0)703 230805                 Hampshire
                                                  GU13 8UZ
                                                  Tel: +44 (0)252 811818
                                                  Fax: +44 (0)252 811435

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                              BCS FACS
                       Fifth Refinement Workshop
           Theory and Practice of Formal Software Development
                         8 - 10th January 1992
                               LONDON, UK

     Sponsored by Lloyd's Register, Program Validation Ltd and the DTI


RETURN TO:           Roger Shaw
                     Performance Technology
                     Lloyds Register
                     Lloyd's Register House
                     29 Wellesley Road
                     CRO 2AJ
                     Tel: +44 (0)81 681 4848
                     Fax: +44 (0)81 681

Name:     ..............................................................

Address:  ..............................................................

Registration Fee:     Enclosed    /  Please Invoice  / Assisted place requested*

Encircle applicable figure:
                  FACS Members            Speakers             Others
Fee Enclosed       125 pounds            125 pounds           140 pounds
Please Invoice     135 pounds            135 pounds           150 pounds

These prices include VAT. Cheques should be made payable to BCS FACS.

Special dietary requirements  ...........................................

Tick if accommodation at City University is required: ..................

If so circle required dates:     7        8        9  January 1992

(unless otherwise specified, one single room will be reserved)

Tick if you would like a list of local hotels: .........................

Any other information you think you will need:..........................

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