CompTIA A_ Certification All-In-One Exam Guide, Seventh Edition - Michael Meyers [463]
Network Security
Networks are under threat from the outside as well, so this section looks at issues involving Internet-borne attacks, firewalls, and wireless networking. This content is the security bread and butter for a CompTIA A+ technician, so you need to understand the concepts and procedures and be able to implement them properly.
Malicious Software
The beauty of the Internet is the ease of accessing resources just about anywhere on the globe, all from the comfort of your favorite chair. This connection, however, runs both ways, and people from all over the world can potentially access your computer from the comfort of their evil lairs. The Internet is awash with malicious software—malware—that is, even at this moment, trying to infect your systems. Malware consists of computer programs designed to break into computers or cause havoc on computers. The most common types of malware are grayware, spam, viruses, Trojan horses, and worms. You need to understand the different types of malware so you can combat them for you and your users successfully.
Grayware
Programs that intrude unwanted into your computing experience but don’t actually do any damage to your systems or data—what’s called grayware—can make that computing experience less than perfect. On most systems, the Internet Web browser client is the most often used piece of software. Over the years, Web sites have come up with more and more ways to try to get you to see what they want you to see: their advertising. When the Web first got underway, we were forced to look at an occasional banner ad. In the past few years, Web site designers have become much more sophisticated, creating a number of intrusive and irritating ways to get you to part with your money in one form or another.
There are basically three irritating grayware types: pop-ups, spyware, and adware. Popups are those surprise browser windows that appear automatically when you visit a Web site, proving themselves irritating and unwanted and nothing else. Spyware, meanwhile, defines a family of programs that run in the background on your PC, sending information about your browsing habits to the company that installed it on your system. Adware is not generally as malicious as spyware, but it works similarly to display ads on your system. As such, these programs download new ads and generate undesirable network traffic. Of the three, spyware is much less noticeable but far more nefarious. At its worst, spyware can fire up pop-up windows of competing products on the Web site you’re currently viewing. For example, you might be perusing a bookseller’s Web site, only to have a pop-up from a competitor’s site appear.
Pop-Ups Getting rid of pop-ups is actually rather tricky. You’ve probably noticed that most of these pop-up browser windows don’t look like browser windows at all. They have no menu bar, button bar, or address window, yet they are separate browser windows. HTML coding permits Web site and advertising designers to remove the usual navigation aids from a browser window so all you’re left with is the content. In fact, as I’ll describe in a minute, some pop-up browser windows are deliberately designed to mimic similar pop-up alerts from the Windows OS. They might even have buttons similar to Windows’ own exit buttons, but you might find that when you click them, you wind up with more pop-up windows instead! What to do?
The first thing you need to know when dealing with pop-ups is how to close them without actually having to risk clicking them. As I said, most pop-ups have removed all navigation aids, and many are also configured to appear on your monitor screen in a position that places the browser window’s exit button—the little X button in the upper-right corner—outside of your visible screen area. Some even pop up behind the active browser window and wait there in the background. Most annoying! To remedy this, use alternate means