Software systems context
- 1. Software systems context Taufik Hidayat Sistem informasi Uin suska riau
- 2. Testing Principle - Testing is context dependent Testing is done differently in different contexts. For example, safety-critical software is tested differently from an e-commerce site. These days, almost everyone is aware of software systems. We encounter them in our homes, at work, while shopping, and because of mass-communication systems. More and more, they are part of our lives. We use software in day-to-day business applications such as banking and in consumer products such as cars and washing machines. However, most people have had an experience with software that did not work as expected: an error on a bill, a delay when waiting for a credit card to process and a website that did not load correctly are common examples of problems that may happen because of software problems. Not all software systems carry the same level of risk and not all problems have the same impact when they occur. A risk is something that has not happened yet and it may never happen; it is a potential problem. We are concerned about these potential problems because, if one of them did happen, we'd feel a negative impact. When we discuss risks, we need to consider how likely it is that the problem would occur and the impact if it happens. For example, whenever we cross the road, there is some risk that we'll be injured by a car. The likeli- hood depends on factors such as how much traffic is on the road, whether there is a safe crossing place, how well we can see, and how fast we can cross. The impact depends on how fast the car is going, whether we are wearing protective gear, our age and our health. The risk for a particular person can be worked out and therefore the best road-crossing strategy.
- 3. Some of the problems we encounter when using software are quite trivial, but others can be costly and damaging - with loss of money, time or business reputation - and even may result in injury or death. For example, suppose a user interface has typographical defects. Does this matter? It may be trivial, but it could have a significant effect, depending on the website and the defect: 1. If my personal family-tree website has my maternal grandmother's maiden name spelt wrong, my mother gets annoyed and I have to put up with some family teasing, but I can fix it easily and only the family see it (probably).
- 4. 2. If the company website has some spelling mistakes in the text, potential customers may be put off the company as it looks unprofessional. 3. If a software program miscalculates pesticide application quantities, the effect could be very significant: suppose a decimal point is wrongly placed so that the application rate is 10 times too large. The farmer or gardener uses more pesticide than needed, which raises his costs, has environmental impacts on wildlife and water supplies and has health and safety impact for the farmer, gardener, family and workforce, livestock and pets. There may also be consequent loss of trust in and business for the company and possible legal costs and fines for causing the environmental and health problems.