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Ariane 5 explosion. Pentium FDIV bug. 66 MHz Intel Pentium (sSpec=SX837) with the FDIV bug The error was discovered by Professor Thomas R.

Pentium FDIV bug

Nicely at Lynchburg College, Virginia, USA.[2] Chronology[edit] On October 30, 1994, Nicely sent an email describing the error he had discovered in the Pentium floating point unit to various contacts, requesting reports of testing for the flaw on 486-DX4s, Pentiums and Pentium clones.[2] This flaw in the Pentium FPU was quickly verified by other people around the Internet, and became known as the Pentium FDIV bug (FDIV is the x86 assembly language mnemonic for floating-point division). The story first appeared in the press on November 7, 1994, in an article in Electronic Engineering Times, "Intel fixes a Pentium FPU glitch" by Alexander Wolfe.[4] The story was subsequently picked up by CNN in a segment aired on November 21, 1994.[2] This brought it into widespread public prominence. Affected models[edit] Virtual Case File.

Virtual Case File (or VCF) was a software application developed by the United States Federal Bureau of Investigation (FBI) between 2000 and 2005.

Virtual Case File

The project was officially abandoned in April 2005, while still in development stage and cost the federal government nearly $170 million. In 2006, the Washington Post wrote "In a 318-page report, completed in January 2005 and obtained by The Post under the Freedom of Information Act, [the Aerospace Corporation] said the SAIC software was incomplete, inadequate and so poorly designed that it would be essentially unusable under real-world conditions. Mars Climate Orbiter. The Mars Climate Orbiter (formerly the Mars Surveyor '98 Orbiter) was a 338 kilogram (750 lb) robotic space probe launched by NASA on December 11, 1998 to study the Martian climate, atmosphere, surface changes and to act as the communications relay in the Mars Surveyor '98 program, for Mars Polar Lander.

Mars Climate Orbiter

However, on September 23, 1999, communication with the spacecraft was lost as the spacecraft went into orbital insertion, due to ground-based computer software which produced output in non-SI units of pound-seconds (lbf×s) instead of the metric units of newton-seconds (N×s) specified in the contract between NASA and Lockheed. The spacecraft encountered Mars on a trajectory that brought it too close to the planet, causing it to pass through the upper atmosphere and disintegrate.[1][2] Mission background[edit] Therac-25. The Therac-25 was a radiation therapy machine produced by Atomic Energy of Canada Limited (AECL) after the Therac-6 and Therac-20 units (the earlier units had been produced in partnership with CGR of France).


It was involved in at least six accidents between 1985 and 1987, in which patients were given massive overdoses of radiation, approximately 100 times the intended dose.[2]:425 These accidents highlighted the dangers of software control of safety-critical systems, and they have become a standard case study in health informatics and software engineering. Problem description[edit] The machine offered two modes of radiation therapy: Direct electron-beam therapy, which delivered low doses of high-energy (5 MeV to 25 MeV) electrons over short periods of time;Megavolt X-ray therapy, which delivered X-rays produced by colliding high-energy (25 MeV) electrons into a "target".

Root causes[edit] The Home of Load Testing. Test Case Format. Process impact: This reference page documents the format of test cases and gives tips on writing test cases.

Test Case Format

You can copy and paste the sample test case into your test-cases.html file. This file itself should not be edited to hold specific test cases. This test case format is suitable for manual system test cases. The test cases should be written in enough detail that they could be given to a new team member who would be able to quickly start to carry out the tests and find defects. Format of test steps Each step can be written very tersely using the following keywords: Getting Started with loadUI. Try the full experience of Pro: Video Tutorial The first view that you will see when you open LoadUI is the Workspace View.

Getting Started with loadUI

This is where you manage your projects. The Workspace View. Create a new Project by dragging the New Project icon to the project list. Creating a Project using drag and drop. Now, in the Create New Project dialog, enter a name for the new project, and click Create. Testing Checklist. CWE - 2011 CWE/SANS Top 25 Most Dangerous Software Errors. Summary Discussion Salt might not be good for your diet, but it can be good for your password security.

CWE - 2011 CWE/SANS Top 25 Most Dangerous Software Errors

Instead of storing passwords in plain text, a common practice is to apply a one-way hash, which effectively randomizes the output and can make it more difficult if (or when?) Attackers gain access to your password database. If you don't add a little salt to your hash, then the health of your application is in danger. Prevention and Mitigations Related CWEs Related Attack Patterns CAPEC-IDs: [view all]16, 20, 49, 55, 97 Monster Mitigations. Web Testing Software. Software Testing Complete Guide.