How Do You Know when a Download is Safe?For a couple of years I have presented a course on How to Download Nifty Things from the Internet Safely for senior computer users. The course has two parts: (1) establishing that some pretty nifty things are available for free, and (2) there are ways to reasonably protect yourself against simultaneously downloading some unwanted trouble along with the desired application.

The course looks at freebies ranging from whole operating systems (mostly Ubuntu) through complete office suites (several available: we emphasize LibreOffice) to trivial eye candy like Iconoid, which turns desktop icons transparent after a mouse is inactive for 20 seconds and brings them back upon detecting mouse motion. Along the way, we also examine search engines and browsers, which qualify as things we get from the Internet for free. Establishing the availability of quality applications that can be downloaded for free is not as easy as you might expect. When showing a class the variety of offerings on SourceForge, they always look puzzled and ask questions about the open source community.

Establishing the availability of useful things is relatively easy. But the meat of the course, and the more difficult part to present, is how to distinguish between quality downloads and unwanted or potentially harmful packages. These are often students who routinely open attachments on forwarded emails without hesitation, but are often afraid to download obviously benign applications because they have heard so many horror stories.

Because I have developed my own ways of trying to download material safely (with occasional mishaps like when I picked up an unwanted Babylon toolbar and had real difficulties getting rid of it), I was interested in a recent TED lecture by Markham Nolan that examines a closely related problem: how do we know if information posted is true, and how can a person reasonably wade through the overwhelming flow of uploaded material to find useful stuff?

Nolan approaches this problem as a journalist mining the Internet for breaking news. At first, you might think this is a long way from trying to decide whether to download and install freebie applications, but the underlying issues are the same: filter the data stream to find what you want and then validate it. The main differences are the tools used to determine the credibility of a source and the volume of data.

Recently I had a chance to watch how I approached the problem of finding something I wanted on the Internet. Windows 8 has a nice feature of allowing a desktop wallpaper to span across two monitors rather than repeating the same image on both as is more common. “That’s cool,” I thought, “now where can I get some nice panoramic images to use?” Within minutes, I had found several sources from sites that my handy WOT (Web of Trust) add-on indicated were probably safe. But that is not sufficient since malware can be hidden in jpg images. Call me a worrywart, but I also manually scan pictures that I download. I now have a pleasing custom desktop theme that cycles though several panoramic nature scenes. The total cost was nothing, and if some of the desktops have a discrete logo or faint watermark with a URL leading back to the site where I can pay to download a bigger variety, that is okay and a fair trade.

The first rule of safe downloading is to establish realistic expectations. That is true whether you want to download applications or information. The second rule is that realistic expectations evolve quickly. I never teach the same course twice because the availability of stuff and the associated hazards on the Internet change.

By the way, if you clicked on any of the hot links above, you are following one of the tips I give to students: if someone you know recommends it, and they are trustworthy, then they are acting as a pre-filter for your exploration. This does not mean that everything I link to is safe; it only means that I think the links I put up are safe. It is up to you to decide how reliable I am. Notice I did not provide a link to the Babylon toolbar (a red indication from WOT), although I could have provided many links to instructions for how to get rid of it (green indications on WOT).

Do you have a system of your own for cutting the wheat from the chaff on the Internet? Please leave a comment below and share it with us.

Image: Warning by karl.herler via Flickr