RISKS-LIST: Risks-Forum Digest Friday 15 December 2006 Volume 24 : Issue 51 ACM FORUM ON RISKS TO THE PUBLIC IN COMPUTERS AND RELATED SYSTEMS (comp.risks) Peter G. Neumann, moderator, chmn ACM Committee on Computers and Public Policy ***** See last item for further information, disclaimers, caveats, etc. ***** This issue is archived at <http://www.risks.org> as <http://catless.ncl.ac.uk/Risks/24.51.html> The current issue can be found at <http://www.csl.sri.com/users/risko/risks.txt> Contents: Bloomington bank night depositors victims of old fashioned fishing (David Zawislak) Trig error checking (Martin Ewing) Re: A380 delivery delays (Peter B. Ladkin) Re: Flat train wheels (Peter B. Ladkin) Re: Yet another canceled public sector IT project (Gary Hinson, Richard Karpinski, Jack Ganssle, Rex Black, Richard Karpinski) Re: Slade on "Kim" (Michael Bacon) Abridged info on RISKS (comp.risks) ---------------------------------------------------------------------- Date: Sun, 10 Dec 2006 18:04:27 -0600 From: David Zawislak <davidzawislak@private> Subject: Bloomington bank night depositors victims of old fashioned fishing The Bloomington, Indiana Fifth Third Bank, learned that the Internet is not the only way to be a fishing victim. Up to 11 depositors who used the night deposit slot had their deposits fished out of the slot, after one of the slot's metal security pieces had been sheared off and the bags fished out. <http://www.theindychannel.com/news/10473879/detail.html> [The article notes that a dowel rod was found next to the broken metal piece, with fishing line and a fish hook attached. No bait was required. No switch either. No need to spare the rod. No reel-time problems. No social engineering. Just a straightforward low-tech approach. It reminds us of the futility of believing in high-tech solutions that can be so easily bypassed. PGN] ------------------------------ Date: Sun, 10 Dec 2006 15:27:13 -0500 From: Martin Ewing <m.ewing@private> Subject: Trig error checking (Re: McIlroy, RISKS-24.49) Doug McIlroy's report of the effect of missing punched cards on trig accuracy (RISKS-29.49) brought to mind another troubling trig episode. In the early 1990's, we were heavy into scientific calculations on the Digital VAX-11/780 -- ephemerides which required every last drop of precision. Sometimes the answers weren't checking out. Eventually we found that our VAX floating point unit (a very large circuit board) was malfunctioning. It gave slightly wrong results, but quietly - there were no system error reports. The diagnostic was that sin**2 + cos**2 was intermittently not quite equal to 1 for various arguments. [NOTE: This is a positive example of circular reasoning! PGN] Field service got us new boards, but how could we have confidence this bug was not recurring? In the end we ran a background routine that checked sin**2 + cos**2 forever. (Today, we would make it a screensaver program.) There is a RISKS issue -- how do you know your CPU is giving good results? There aren't any check bits for trig functions. (Alluded to in RISKS-16.68.) ------------------------------ Date: Wed, 13 Dec 2006 18:56:06 +0100 From: "Peter B. Ladkin" <ladkin@private-bielefeld.de> Subject: Re: A380 delivery delays (Ladkin, RISKS-24.45) In RISKS-24.45, I reported that Bloomberg News and AEC News were saying that Hamburg was working with CATIA Version 4 CAD-CAM SW, and Toulouse with CATIA Version 5. Now comes a different story. Nicola Clark wrote an extensive article on the A380 delivery problems in the *International Herald Tribune* this week, in which she states that the Hamburg design SW was in fact made by a U.S. company, Computervision, and dated from the 1980s. If this is so, it isn't simply a file-format problem, as one could suppose with different versions of the same SW. The article is available at www.iht.com/articles/2006/12/11/business/airbus.php Peter B. Ladkin, Causalis Limited and University of Bielefeld www.causalis.com www.rvs.uni-bielefeld.de ------------------------------ Date: Wed, 13 Dec 2006 18:42:45 +0100 From: "Peter B. Ladkin" <ladkin@private-bielefeld.de> Subject: Re: Flat train wheels (PGN, RISKS-24.47) In RISKS-24.47, PGN reported on trainset availability problems in NY/NJ, resulting from maintenance backups in replacing/retruing wheels which had flattened. In Fall, in areas with deciduous trees, a slippery film deriving from mulched fallen leaves can build up on rails. When trains accelerate or brake on rails with such a film, adhesion is much reduced and wheels can slip. The wheel tires (most trains have steel tires on wheels) can develop flat spots through rubbing at places where a slipping wheel comes to a patch with good adhesion and the speed of the wheel does not match the train speed over the rail. It is also not so good for the rails, but they are less affected. This problem is as old as railways. What is new is the computer dimension. In Fall 2003, the German Railways (Deutsche Bahn, DB) had problems with its new electrical multiple units (EMUs, as they are called in England; I use the word "trainsets" henceforth), which have designators ET 423 - 426 depending on their use. The ET 425 series trainsets for regional trains in the Ruhr valley and eastwards through Bielefeld to Minden and Ostwestfalen-Lippe were having serious problems of two sorts. First, ET 425 units, which under dry conditions have extremely good braking characteristics, were overshooting their allowable braking distances in slippery conditions. Since signalling, allowable line speeds, and operations in general depend upon trains being able to stop within a specified braking distance (defined by a braking performance curve), this presented a safety issue. Various incidents had trains passing their stopping point by some hundreds of meters; clearly unacceptable. Second, train wheelsets were developing flat spots at a much higher rate than anticipated and there were not enough replacement sets on hand to be able to keep the required number of trainsets in service. The result was chaos in commuter and regional train service. The trainsets were restricted to maximum speeds of 80 kilometers per hour (kph), half that to which they are certified. They could not maintain the timetable at these slower speeds, and certain trains traveling longer distances had to be turned into two trains at a suitable breakpoint: the second train departed the breakpoint at the timetabled time, with the first train arriving later at the breakpoint, leaving travelers who previously traveled on one train through that point on their journey then to take two: the first one to the breakpoint, arriving late, and a second, later, one from the midpoint onwards, causing a large increase in journey time for these unfortunate and unhappy people. And the Ruhr is the largest urban conglomeration in Germany, so there were lots of them. Some of the trains serviced with ET 425 trainsets were replaced with locomotive-hauled sets, which with their heavier carriages were less susceptible to the problem, and could travel at their posted speeds even in the lower-adhesion conditions. In 2004, the DB planned the trainset replacement on the most heavily affected lines in Fall from the outset, and delays were much reduced, although travelers were not as happy as they would have been with the originally-offered service. I discussed the issues extensively in early 2004 with the railway engineer Oliver Lemke at the Institute for Railway Engineering and Traffic Safety at the Technical University of Braunschweig, and again in early 2005, and Fall 2005. The information below specifically on the ET 425 problem comes mainly from Oliver and from the technical article "Neue Erkenntnisse zum Gleitschutzverhalten elektrischer Triebzüge" (translated: "New Findings on the Antislip Behavior of Electric Trainsets") by K.-R. Hase, S. Müther and P. Spiess, in the Eisenbahntechnische Rundschau volume 54, pp 599-610, October 2005, available online at www.eurailpress.com/archiv/artikel.php?id=8339 (I would translate the journal name as: "Railway Technical Review", but that is the name of a different journal, in English, from the same publisher.) First, a word about brakes. There are roughly four different kinds of braking systems in common use on railways. Two of them, friction brakes and regenerative braking, brake the wheels: the first through friction (as in cars and bicycles), the second turns the motor into a generator and thereby the kinetic energy of the train into electricity (and also some heat) which is fed back into the overhead line. On trains which are certified to travel at over 160 kph, brakes acting directly on the rails are required. There are generally two kinds. Eddy-current brakes consist of electromagnets which hover some millimeters above the rail. The moving electromagnet produces an eddy current in the rail, which produces a force on the electromagnet, and thereby on the trainset to which it is attached, in the opposite direction to that of travel. Eddy-current brakes are used on very-high-speed trains to brake from high speeds, and they are relatively ineffective at lower speeds. The kinetic energy is dissipated largely as heat, and some applications have been said to have set the rails glowing. (I understand that eddy-current braking is also being investigated for road trucks.) Second, there are magnetic rail brakes, which are also electromagnets, but use the magnetic attraction to set themselves firmly on the rail and achieve their braking effect through friction (which also generates heat, of course). The ET 425 units are light, and depend for various reasons more on regenerative braking than other units. For technical reasons, it is harder under regenerative braking to start a halted and sliding wheel rolling again. The ET 425 series was not certified to travel at higher than 160 kph, so did not require rail brakes. Magnetic rail brakes would have solved the braking underperformance problem directly, but the bogies (the chassis which holds the wheel sets, including the wheel sets. In the U.S. they are called "trucks") were not designed to be able to take them. Outfitting the ET 425s with magnetic rail brakes would have entailed replacing bogies, at great cost. (Back in 2005, when I was discussing this, there was a picture of a magnetic rail brake on an ET 425 on the WWW, but it is no longer there.) There was also discovered to be an issue with the sanding devices. These spray sand just in front of the rail-wheel adhesion point to increase adhesion in conditions of low adhesion. The aerodynamics weren't quite right and at high speeds the sand was ending up elsewhere than at the point of adhesion. The braking on the ET 425 trainsets is computer-controlled: brake-by-wire. The driver issues a braking command which consists in a target braking value (in German, "Soll"-Wert), and the computer controller figures out how to attain that value. It turns out that the braking problems were largely solved by optimising the braking algorithms implemented in the control SW. The SW was doing what it should have been doing but the algorithms for braking under non-optimal conditions of friction were not as good as they could have been. I leave it to readers to decide whether this a computer-related problem or rather a computer-related solution to a problem. I suspect the characterisation is a matter of taste. Mark Brader reported a problem in RISKS-23.63 with braking systems on Virgin Trains's then-new Pendolino tilt-trains for the British West Coast Line, a year after the DB problems first surfaced. The BBC carried reports dated 11 November 2004 at news.bbc.co.uk/1/hi/uk/4002257.stm Brader's RISKS report referred only to the very-low-speed braking issues, because these were caused by out-of-spec SW issues, but such issues had little to do with the speed limit of 110 mph to which the BBC article also referred. It turns out that the Pendolinos also had problems with braking during leaf-mulch conditions and, unlike DB high-speed units, were neither required to be fitted with magnetic rail brakes, nor were they so fitted. (I no longer have a suitable reference for this.) Peter B. Ladkin, Causalis Limited and University of Bielefeld www.causalis.com www.rvs.uni-bielefeld.de ------------------------------ Date: Mon, 11 Dec 2006 11:55:09 +1300 From: "Gary Hinson" <Gary@private> Subject: Re: Yet another canceled public sector IT project (R-24.49) Richard has picked out just one of many important issues that commonly affect software development projects, perhaps implying that if only this one issue were addressed, everything would be fine. If so, that's silver bullet thinking. The Real World(TM) is far more complex, for examples: * Small projects are less risky than large ones since they are more predictable and controllable. It is sound advice to split huge monolithic projects into phases and/or to treat them as programmes containing multiple sub-projects that are, as far as possible, mutually independent. Unfortunately, some systems (such as national health systems) are inherently huge and complex, and are extremely difficult to subdivide. There are also additional costs to subdividing projects. Programme management is a more abstract, specialist and hence expensive form of project management (qualified and successful programme managers are in high demand). There are always residual dependencies between sub-projects meaning additional planning and execution risks; * Large projects invariably involve politics, whether national or corporate/internal. There are numerous vested interests, differing aims and competing priorities. This is a given. Dealing effectively with the politics is more art than science; * Richard identified changing requirements specifications, fair enough. Many other aspects of projects often change too, such is the nature of project risk and planning. It makes sense for management to anticipate the likelihood of changes and put in place, in advance: (a) contingency arrangements; and (b) the project governance structures to work proactively with whatever crops up rather than reactively picking up the pieces; and yet there is a curious faith in pre-cast plans, budgets and teams. I am fond of the concept of constantly revising the business case for major projects as they proceed from concept to delivery since the initial case prepared for budgeting purposes is highly unlikely to reflect fully the 'as built' system, both in terms of the costs and the benefits. A useful side-effect is that from the highly refined business case emerges a comprehensive blueprint for metrics to measure and maximize the value obtained from the delivered system (read John Thorp's "The Information Paradox" for more); * Projects are themselves change activities, introducing the thorny topic of change management. We persist in referring to "software development projects" etc. rather than "organizational change initiatives" etc. The organization is of course going to be different post-implementation, significantly different in the case of large systems. Managing the transition from pre- through para- to post-implementation is no easy task but seldom (in my experience) is it truly recognized by management as an important and difficult activity, at least until things are already going seriously wrong. The more organizational and political layers there are between developers and users, the harder it is to ensure that the project sponsor's change vision is both appropriate/feasible and reflected on the ground; * There will always be conflicting priorities for senior management's attention. If there were not, there would be a greater risk of management 'going native' on the project, perhaps losing sight of the true business objectives and changes in the environment. On top of that, we all have different skills and motivations. The more people are involved in a project, the more diversity of views and opinions there will be. It seems to me that management by and large needs to be more creative, professional and flexible with respect to the governance of large projects. Why not, for instance, initiate multiple parallel project teams in friendly competition to develop the best business case and project plans? Management can monitor their progress, seed good ideas between the teams and when appropriate kill off the weakest to focus resources on the most promising (my hero Charles Darwin coined the term 'survival of the fittest'). Sure there would be higher costs up front but the risk mitigation and competitive motivation may more than compensate. 'Extreme programming' techniques, object orientation, formal methods, outsourcing etc. all potentially have their place in a creative organization that is prepared to experiment and learn. Traditional stick-in-the-mud management teams are destined to repeat the same failures over and over, and perhaps worse to stall vital projects because of the fear of failure (the risk of not doing what's necessary). Leaning brings me to my final point. Every project, good and bad, is a worthwhile learning opportunity. Those directly involved clearly learn from the experience (subject to the limitations of their own perspectives) but it is probably worthwhile spreading the knowledge further afield. Internal Audit has a valuable role both to review and advise on the political, risk and project management during the project and to tease out and share the lessons to be learnt afterwards. Doing this repeatedly improves Internal Audit's competence and expertise. Dr Gary Hinson PhD MBA CISSP CISM CISA, CEO IsecT Ltd. +64 634 22922 www.NoticeBored.com www.IsecT.com www.ISO27001security.com ------------------------------ Date: Sun, 10 Dec 2006 17:15:33 -0800 From: Richard Karpinski <dick@private> Subject: Re: Yet another canceled public sector IT project (R-24.49) Gary, If it were one issue, it wouldn't have taken Gilb 474 pages to address the rather broad topic of project management. Would you like to see the PDF to understand how thoroughly he approaches the problems? I just tried to say the essential parts in a short enough form that people could read it through. It was brief. How can you do it with extreme incrementalism and not know you are failing before you have spent ten percent of the budget? I boldly claim that you cannot. I further claim that that fact justifies my claim that the horrors of the current methods can be reliably averted by adopting extreme incrementalism. Ask Gilb or Malotaux about their experience with it. P.S. In fact, here is what Niels Malotaux said in response to my item: Nice to hear from you. And all true. Every time a project gets in trouble, I ask myself: "Why didn't they just ask for a bit of help?" It's SO easy to get a project on track and let it conclude successfully, that it must be either ignorance (which it mostly is) or lack of interest (which it mostly seems to be) when people let projects fail again and again. You say: "... evolutionary method is still considered radical and risky". I regularly get the comment that what I say is "highly controversial and philosophical". Still, we know from practice that it is highly practical and successful. Recently I saw again two project managers very reluctant to start letting me help getting their failing projects on track. Only because their boss gave them the choice to either from now on pass every milestone on time themselves (which they have never done before), or to let me help them, they reluctantly conceded to let me help them. Within on week, just only applying the TaskCycle, they were convinced that this was great and helping them immensely to be more successful. So I was thinking: "Why can't I explain people convincingly about the Evo benefits before starting?". I think that before starting eating the pudding, people have no clue what we are talking about. A lack of frame of reference. People just don't hear what we are saying. Besides, what we are saying is so simple that it cannot be true. Still a big marketing problem. So many projects that can be saved and hardly anybody understanding that we can do something about it. Niels ------------------------------ Date: Mon, 11 Dec 2006 08:05:19 -0500 From: Jack Ganssle <jack@private> Subject: Re: Yet another canceled public sector IT project (R-24.49) Richard Karpinski complained that projects fail when we expect to be able to nail down all of the requirements up front, rather than embrace an incremental approach as advocated by Tom Gilb and many others. Yet this reflects the essential tension in software development. He's right; realistically it's hard and sometimes impossible to understand the requirements early in the project. Yet he's wrong: management needs a price, up front, to decide if the project is at all affordable, and if the promised value exceeds development costs. Management needs a date, up front, to know if the product will hit the market window. We can waffle and promise to deliver a range of dates and costs, or we can protest mightily that such expectations are unreasonable. Yet if the project is late, so there's no revenue being generated, and as a result our paycheck is a dollar short or a day late, we go ballistic. Alas, I fear this conundrum will never be resolved. Jack Ganssle, jack@private 410-504-6660 Skype jack.ganssle ------------------------------ Date: Tue, 12 Dec 2006 08:05:42 +1300 From: Rex Black <rexblack@private> Subject: Re: Yet another canceled public sector IT project (R-24.49) I have a great deal of respect for Tom Gilb, who I consider a personal friend as well as an esteemed colleague. Also, I realize that these iterative lifecycle models are very popular right now. That said, this heavy emphasis on these types of lifecycle models represent the latest manifestation of what Fred Brooks described as software engineering's "silver bullet" quest. A number of years ago, during the deflation of the 4GL bubble, which, ironically, overlapped the early days of object-oriented languages, Boris Beizer wrote mockingly in Latin about the "lingua salvator est" tendency, a desire to see the adoption of the right language as the magic solution, the savior, the discovery that would make all our problems go away. And, while we're on that note, CMM and TQM, anyone? I am not saying that good languages, good processes, and a focus on quality are useless. I am saying that holding any *one* thing out as a solution is counter-productive at best. Software engineering is hard for a number of reasons. Some of those reasons result from doing things we (collectively) know to be stupid. Others result from dogmatically following approaches laid out by others without regard for how to tailor those approaches to our situation. Let's not pretend that something as simple as a lifecycle model is going to solve all our problems, particularly when the real magic of a lifecycle model--if there is any magic in it--lies in tailoring it to what we really need. Amer. Software Testing Qualifications Board, Int'l Software Testing Qual. Board,... Bulverde, TX 78163 USA +1-830-438-4830 www.rexblackconsulting.com ------------------------------ Date: Tue, 12 Dec 2006 16:20:24 -0800 From: Richard Karpinski <dick@private> Subject: Re: Yet another canceled public sector IT project (Black, R-24.49) > That said, this heavy emphasis on these types of lifecycle models > represent the latest manifestation of what Fred Brooks described as > software engineering's "silver bullet" quest. Tom Gilb, in his 474 page "Competitive Engineering" is not offering a silver or magic bullet but rather a fleet of magic bulldozers, viewing lenses, decision processes, evaluation techniques, and an overarching focus on delivering measured value to identified stakeholders, including the users of the proposed system. The radically small steps allowed between instances of facing reality again, with usable deliveries to stakeholders, guarantees that if failure occurs, then it happens clearly in the first tenth of the project, not hidden until years of effort have been invested. > A number of years ago, during the deflation of the 4GL bubble, which, > ironically, overlapped the early days of object-oriented languages, The early days of object-oriented languages was the mid 1960's for me with SIMULA-67. > Boris Beizer wrote mockingly in Latin about the "lingua salvator est" > tendency, ... We have never before had a system like Planguage, where the magic was so thoroughly inspected, evaluated, guided, and verified in routine use of a "single" "language". > And, while we're on that note, CMM and TQM, anyone? You won't get me to disdain TQM since it seems to me that that is pretty close to SQC as advocated to such success in Japan by W. Edwards Deming whom I respect greatly. > ... I am saying that holding any *one* thing out as a solution is > counter-productive at best. If you think Competitive Engineering is one thing, or that Tom's Planguage is just a good language for designing a project, then you need to read more of those 474 pages. > Software engineering is hard for a number of reasons. ... Which is exactly why the non-simple approach taken in Competitive Engineering is both demanding and successful. The very essence of the method is the focus on tailoring to the actual circumstances and measuring the success of applying engineering effort toward the identified measurable business goals of the project. In order to take advantage of all that tailoring and measuring, it is absolutely vital to avoid even medium sized development cycles. Obviously, the best approaches will naturally avoid doing the things we know to be stupid. Since fixing the steps of the project at the very beginning is one of those really stupid ideas, I felt the need to rail against it. But I had to do it in a page or so to be published and read. My view is that we actually will need many more pages than Tom used to explain his approach so that it can be understood without intense consideration of each paragraph. But he had to do it in a form that could still be lifted without violating OSHA rules even when made manifest on printed paper. Perhaps I'm unfairly picking on what you said. Clearly, I have some skill in treading on people's toes, despite a lack of conscious intent. Would you care to check in with Tom or Kai or Niels Malotaux to see what they say about your assertions? Richard Karpinski, World Class Nitpicker 148 Sequoia Circle, Santa Rosa, CA 95401 dick@private Home +1 707-546-6760 Cell +1 707-228-9716 ------------------------------ Date: Mon, 11 Dec 2006 12:21:34 +0000 From: attilathehun1900@private Subject: Re: Slade on "Kim" (RISKS-24.49) Rob Slade hits it right on the nose with his review of Rudyard Kipling's "Kim". Kipling was definitely one of us. In his "Just So Stories", he provided his "Six Honest Serving Men", the key question starters that every information security analyst and auditor worth their salt always uses: "I keep six honest serving-men (They taught me all I knew); Their names are What and Why and When And How and Where and Who" Michael "Streaky" Bacon [Brent J. Nordquist notes that Project Gutenberg has the free E-text. PGN ] <http://www.gutenberg.org/etext/2226> ------------------------------ Date: 2 Oct 2005 (LAST-MODIFIED) From: RISKS-request@private Subject: Abridged info on RISKS (comp.risks) The ACM RISKS Forum is a MODERATED digest, with Usenet equivalent comp.risks. => SUBSCRIPTIONS: PLEASE read RISKS as a newsgroup (comp.risks or equivalent) if possible and convenient for you. 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Lindsay has also added to the Newcastle catless site a palmtop version of the most recent RISKS issue and a WAP version that works for many but not all telephones: http://catless.ncl.ac.uk/w/r <http://the.wiretapped.net/security/info/textfiles/risks-digest/> . ==> PGN's comprehensive historical Illustrative Risks summary of one liners: <http://www.csl.sri.com/illustrative.html> for browsing, <http://www.csl.sri.com/illustrative.pdf> or .ps for printing ------------------------------ End of RISKS-FORUM Digest 24.51 ************************
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