Tried & Tested

There are various approaches to testing, depending on the type of requirements being checked. Larry Decklever, president of BenchmarkQA, a software testing company in Bloomington, says the following types of software testing are common. Terminology may differ from company to company.

Functional testing answers the fundamental question: Does the application do what it’s supposed to do?

Load or performance testing looks at an application’s responsiveness. How fast is it? Can it handle lots of users?

Compatibility testing addresses how software works on different systems. “Sometimes an application has to work the same on multiple platforms,” Decklever says. “Let’s say its a Web application or e-commerce. In that case, you’re looking at individuals who could have different operating systems and different browsers. You need to verify that the application is going to work in all these different scenarios.”

System testing is for applications with many pieces. “For instance, you’ve got a large application comprised of multiple modules with multiple subsystems,” Decklever says. When checking all of the modules together as a whole, it’s referred to as system testing.

User acceptance testing gets feedback from the real end users. This is where “the user gets the opportunity to accept the application from IT,” Decklever says. “To say, ‘Yes, this works how we want it to work.’”

Destructive testing verifies if the application can identify errors and handle unusual situations, such as invalid data.

Ad hoc testing often takes the form of rounding up users to essentially “try out” the software. Not every requirement is checked.

Some testing types may take priority, depending on the systems being addressed. “Compatibility testing is becoming really big now,” Fox says. “Let’s say you have a Web application and you want to make sure it works on the Mac, and all of the different browsers on the Mac, and all of the different operating systems on the Mac. And then for Windows, you’ve got Windows Vista and XP, and 64 bit and 32 bit, and you’ve got different browsers. You want to make sure your application works in all of these different environments.” Fox notes that compatibility is especially important for public-facing e-commerce Web sites.

One of Swat’s clients, a sports equipment and apparel company, sells a pedometer that plugs into a USB port on a computer and uploads data to the company’s Web site so an athlete can track his or her performance. “We do a lot of compatibility testing for them because we want to make sure that their devices work for any user out there no matter what kind of computer they have, what kind of operating system they’re running, or what kind of browser their using,” Fox says. Other compatibility considerations include testing different firewalls and virus software, and different USB hubs.