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Latest News in Testing, Inspection and Certification

NTS News Center - Latest News in Testing, Inspection and Certification

Remote Access using VNC

Control Your ComputerIt’s 6 p.m. and that automated test script is still running on your test platform. It’s time to go home, but if the test stops for some reason when you’ve left for the night, you’ll have to start all over in the morning. What do you do? Well, if you’ve planned ahead, you can remotely access your test platform using any of a number of remote access/remote control software products.

One of the oldest and most popular remote control programs is VNC. VNC (Virtual Network Computing) provide two small applications, the server (which runs on the target machine) and the viewer (which runs on your local platform), which transmit the keyboard and mouse input from the viewer and return the display from the server as if you were sitting in front of the computer. There are several benefits to VNC:

  • It is is GPL’d software, many versions of which are available for free, including RealVNC, TightVNC, and UltraVNC.
  • It’s been ported to a wide variety of platforms, from Windows to the iPhone and everything in between.
  • Many operating systems use VNC protocols for their remote control (such as Mac OS X’s Remote Desktop and Ubuntu’s Remote Desktop), so you don’t even need to install the server on those platforms
  • VNC Viewer doesn’t require an installation, so you can run it from a USB stick. Plus many VNC servers provide a web interface as well so you should be able to get access from any web browser

However, VNC is not by definition a secure protocol (don’t forget to at least set a password), and is best used through a VPN or SSH connection for security purposes.  In addition, it will also typically require you to open a port in your firewall for access, usually port 5900.

But the benefit of being able to see/control your platform remotely can’t be measured.

Linux – Getting Your Feet Wet

LinuxIf you’re looking to expand your abilities/capabilities as a test engineer, Linux is a good way to become more familiar with Unix-based operating systems. Even if you don’t have an extra computer sitting idle to install Linux on, you can setup and install complete working copies of many Linux distributions (distros) without messing up your current Windows installation.

The easiest way to try out a Linux OS is to download a LiveCD. Many popular distros, including Ubuntu, provide downloadable CD images that can be downloaded, burned, booted up, and used to try out an operating system. Unfortunately, most of these LiveCDs don’t offer the ability to really customize or save your changes to the OS, and they suffer from slow performance due to the limitations of the CD. But you can at least learn a little about the OS, GUI, CLI, etc. Running a LiveCD is kind of like putting your big toe in the water.

If you’d like another easy way to try out different distros of Linux, you can also install VMware Player (free) and download one of the many pre-built virtual machines from the Virtual Appliance Marketplace, including openSUSE, Damn Small Linux, Ubuntu, Fedora, and Mandriva. Then all you need to do is run the VMware Player and select a virtual appliance to run. There is a performance hit running the operating systems in a virtual machine, but it’s very easy to get started – all you really have to do is download the VM you want to run. Everything is already setup and configured. Plus you’ll have the ability to save changes and gain a more detailed understanding of running Linux.

If you’d like to really get a good idea of how a popular distro like Ubuntu (or one of it’s flavors, like Kubuntu or Xubuntu) actually runs on your computer, you can download Wubi which provides an easy Windows based installer. It installs Linux like a normal application in Windows, configures a boot manager, and sets up a virtual hard drive for you to use. The great thing is you don’t have to worry about hard drive partitions or complicated setups. And, when you are done using the software, you can simply uninstall from within Windows and it will erase the virtual hard drive file and free that space back up almost instantly. It’s really a good way to jump into Linux without the configuration hassles, but with almost full-speed performance, and the ability to quickly revert back to Windows.

How To Securely Erase A Hard Drive

How to securely erase a hard drive - the hard wayWhen you’re doing lots of quality assurance testing for other companies, security becomes an important component. No one wants to lose business because they accidentally leak product information, even after the testing is complete. To make sure you’re erasing your hard drive securely, you can try Darik’s Boot & Nuke (DBAN). DBAN provides a self-booting disc which allows you to securely delete everything off of a hard drive, and makes the data unrecoverable including to current forensic analysis methods. DBAN is a free download, although they also offer a commercially supported version (EBAN) which includes the necessary support for compliance with SarBox, HIPAA, and FISMA.

The same software also works for those of us who want to clear our hard drives before recycling or selling our computers. Don’t want the new buyer to get our bank or credit card info.

What Web Browsers Should I Test With?

Web BrowsersIn a previous post, we discussed the importance of testing your website with older web browsers. MaximumPC has a very informative article on the latest browsers of today and tomorrow (for Windows primarily) which makes a good starting place if you want to be comprehensive in the compatibility testing you perform. Here’s a summary of the list, along with the January 2009 stats for each from W3Schools:

Stable/Current Releases

Upcoming/Beta Releases

And don’t forget, you can use BrowserShots to generate quick screenshots of your website for review. All of the above browsers, except for Opera 10, are among the browsers that you can get screenshots of.

Bug tracking analysis using SharePoint

Bug TrackingFor many companies, Microsoft Sharepoint has become an important way to communicate and collaborate on projects, including hardware and software development projects. It’s very simple with SharePoint’s custom lists to develop quick bug reporting solutions to meet your internal needs and test methodologies in just a few minutes. However, what most people don’t realize is that SharePoint can also be used in conjunction with Microsoft Excel to perform some rather informative analysis and graphing of your defect tracking data.

The key to everything is the ability of SharePoint to export data to Excel using web queries. You can export the data to Excel and, using the connector, update the data from SharePoint whenever you want (e.g., on opening the spreadsheet, after a set period of time, via a macro button, etc.). It’s incredibly handy and VERY powerful, especially if you’ve any familiarity with some of Excel’s conditional formulas – in particular, COUNTIF.

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Automating Tests – Python & PyVISA

Python & PyVISA

Often in testing, it would be nice to have a way of automating mundane tasks on test equipment without having to dig too deep into proprietary code. Well, if your device has a GPIB/Serial/USB interface,  you’re in luck.  Using Python and PyVISA, you can fairly easily automate tasks using only a few lines of code.

VISA (Virtual Instrument Software Architecture) is an industry standard implemented by several test and measurement companies to simplify development using their equipment. VISA is maintained by the Interchangeable Virtual Instrument Foundation (IVI Foundation), and provides a common API for controlling test instruments from a computer, while PyVISA provides the necessary hooks between Python and the standard VISA library for ease of programming. After installing Python and the PyVISA package, you can start sending VISA commands in just a few lines of code.

An example to call an instrument on a GPIB bus:

import visa
test = visa.instrument("GPIB::12")
#Clear settings on equipment
#Query the identity

Writing (when a reply isn’t required) is simple using the ‘write’ method, and if a reply is required, use the ‘ask’ method.  That’s it! A simple way to quickly develop/automate testing using your test instruments.

History Lesson

The World's First Computer Bug

Back in 1945, engineers running the Harvard Mark II (an early electromechanical computer at Harvard University) found an actual bug in their hardware – literally, a moth that got stuck in a relay was causing problems. Decades later, we’re still finding “bugs” in our computer hardware and software. Wired has an interesting article on their website talking about History’s Worst Software Bugs, including Intel’s Pentium floating point bug which cost them $475 million to repair. Although the article is a few years old, it’s an interesting read.

And the bugs are still continuing today. Just a few months ago, in 2008, Seagate released their 1.5TB Barracuda hard drives with an error that could hang the hard drive during streaming video or low-speed transfers. When they attempted to release a bug fix, they ended up bricking the 500GB Barracudas for other users!

Just remember these “history lessons” before you release your product to market.

Website Compatibility Testing

websitelogosIf you’re putting up a new website, it’s common practice to test your website with older versions of popular web browsers and your “required software” (e.g., Flash, Java, etc.) to make sure it is backward compatible. Even if your website is fully compliant to the latest W3C and CSS standards, it still may look very different in different browser/operating system configurations. For example, if you’ve just put up a new website, you may want to try it out using an old version of Internet Explorer or Firefox, maybe Flash 7 or 8, or an old version of Java. Only one problem – where do you find old versions of the software to install?

If you’re looking for older versions of web browser, try the Evolt Browser Archive. Started in 1999, the Evolt Archive has a large variety of older browsers (including little known ones like Cyberdog and iCab) and older versions of many popular browsers (including Internet Explorer all the way back to 1.0).

You can also find older Windows versions of web browsers and other software (including the Microsoft Java VM and Adobe Flash) at OldVersions.com. If you’re trying to find out what most people are using today, you can visit the Browser Statistics from W3C for the latest browsers, operating systems, display depths, etc.

And rather than trashing your current desktop installation of MSIE or Firefox, grab a copy of VirtualBox and create your own virtual machines to test different web browsers.