When it comes to phone calls, privacy is the most common security concern. Hackers can eavesdrop on VoIP calls to discover the content of participants' conversations. But eavesdropping isn't the only - or, in some cases, even the most serious - security risk you face when using VoIP.

In addition to intercepting the media protocol packets that contain the actual audio, VoIP attackers can target call-signaling protocols or the underlying networking (i.e., TCP/IP) protocols to cause poor call quality or even crash your VoIP devices and network.

Visit TechRepublic and Debra Shinder's article at http://blogs.techrepublic.com.com/security/?p=255 to get a brief look at some of these types of attacks, what makes VoIP vulnerable to them, and how you can protect against them.

Note: Debra Littlejohn Shinder is a technology consultant, trainer and writer. She has authored a number of books on computer operating systems, networking, and security and currently specializes in security issues and Microsoft products. She has been awarded Microsoft's Most Valuable Professional (MVP) status in Windows Server Security.