C ASE S TUDY 1 Software Engineering

S TATISTIC Conducted by Standish Group – IT executives of US companies in different industries 8,380 projects The Standish Group estimated U.S. IT projects wasted $140 billion—$80 billion of that from failed projects—out of a total of $250 billion in project spending Source:

S TATISTIC ( CONT.) average cost overrun = 189% average time overrun = 222%. 61% of originally specified features included  ?

O VER B UDGET “A Home Office IT project run by Bull Information Systems is expected to blow its budget by millions of pounds and is hampered by a restrictive contract, according to a leaked report. The National Audit Office report, due in the Spring, is expected to reveal damning evidence that the project to implement two systems - the National Probation Service Information Systems Strategy, and the Case Record and Management System - for the probation service will cost £118m by the end of the year, 70 per cent over its original budget. “ Source:

O VER B UDGET / O VER S CHEDULE New air traffic system already obsolete: “National Air Traffic Services (Nats) is already looking at replacing the systems at its new control centre at Swanwick in Hampshire, even though the system doesn't become operational until next week. Now running six years late and £180m over budget, the system will control 200,000 square miles of airspace over England and Wales, looking after two million flights a year. It will finally go live on 27 January. “ “But long-term planners are already looking at replacing the systems.” “Swanwick was originally meant to be operational by 1997, but problems with the development of software by Lockheed Martin caused delays, according to Nats.” Source: [ ]

O VER B UDGET / O VER S CHEDULE ( CONT.) … Air traffic control system crashes again [ ]

O VER S CHEDULE Central Provident Fund (CPF) Singapore: a nationwide social security savings program for working Singapore citizens and Permanent Residents “IBM was unable to deliver according to contractual agreements despite extensions to the project deadline” The contract was eventually terminated in 2004 Central Provident Fund (CPF) Board filed a civil suit against IT giant IBM, over the deployment of a software system contracted to the vendor in 2001 Source:

U SABILITY AU$250 million ICS (Integrated Cargo System) to replace one that had been operating for more than 20 years Problems in the system have caused massive delays to container clearances, resulting in a backlog of cargo at some ports Electronic messages had been trapped for up to several hours, slowing clearance of imports and prompting claims from one state minister key NSW ports were within a couple of days of being forced to turn cargo-bearing ships away It is recommended that the sea cargo component of ICS be turned off, and industry revert to the previous system Source:

S AFETY Emergency calls system effectively did away with the radio and telephone calls to stations, with the computer dispatching crews to answer calls. But within hours, during the morning rush, calls were going missing in the system; ambulances were arriving late or doubling up on calls. Distraught emergency callers were also held in a queuing system which failed to put them through for up to 30 minutes. As many as 20 people died. Causes: assumed location of ambulances known, memory leak, operators left out Source:

T HREATS TO H UMAN L IFES Therac-25 medical accelerator: a radiation therapy device The device malfunctions and delivers lethal radiation doses at several medical facilities It could deliver two different kinds of radiation: either a low-power electron beam (beta particles) or X-rays Because of race condition, a quick-fingered typist could accidentally configure the Therac-25 so the electron beam would fire in high-power mode but with the metal X-ray target out of position At least five patients die; others are seriously injured Source:

P ROGRAMMING /T ESTING E RROR Ariane 5: took 10 years and $7 billion to produce At 39 seconds after launch, as the rocket reached an altitude of two and a half miles, a self-destruct mechanism finished off Ariane 5 Cause of error: computer program trying to stuff a 64-bit number into a 16-bit space, causing the rocket to make an abrupt course correction that was not needed, compensating for a wrong turn that had not taken place. The guidance system had in fact shut down 36.7 seconds after launch, when the guidance system's own computer tried to convert one piece of data -- the sideways velocity of the rocket -- from a 64-bit format to a 16-bit format = overflow error.

P ROGRAMMING /T ESTING E RROR ( CONT.) When the guidance system shut down, it passed control to an identical, redundant unit, which was there to provide backup in case of just such a failure. Guess what - the second unit (having the same software) failed too. In an earlier design decision, the programmers had decided that this particular velocity figure would never be large enough to cause trouble. After all, it never had been before. BUT Ariane 5 was a faster rocket than Ariane 4. One extra absurdity: the calculation containing the bug actually served no purpose once the rocket was in the air. Its only function was to align the system before launch. So it should have been turned off. Source:

More on software failures:

H UMAN E RROR EDB Fellesdata AS runs the computer services of about half of Norway's banks. On Thursday 2 Aug 2001, they apparently installed about 280 disks in their Hitachi storage. Then, instead of initializing the new disks, they initialized all their disks -- thereby wiping out the entire warehouse. EDB Fellesdata considering lawsuits Source:

A FTER 10 YEARS... The Standish Group has studied over 40,000 projects in 10 years. Project failures have declined to 15 percent of all projects Projects meeting the “challenged” description— meaning that they are over time, over budget and/or lacking critical features and requirements— total 51 percent of all projects in the current survey. The average project cost overrun in 2004 was found to be 43 percent U.S. projects waste $55 billion from total project spending of $255 billion