Open-Source VNC: Remote Access Made Easy (And Free!)Open-Source VNC: Remote Access Made Easy (And Free!)

There are a lot of great remote access tools available these days, and some of the very best happen to be open-source software. Read on if you would like to learn more about a couple of my personal favorites.Although there are several well-known, open-source remote access tools available today, all of them are based on the same foundation: the Virtual Network Computing (VNC) protocol. Here is what Wikipedia has to say about VNC: In computing, Virtual Network Computing (VNC) is a graphical desktop sharing system which uses the RFB protocol to remotely control another computer. It transmits the keyboard and mouse events from one computer to another, relaying the graphical screen updates back in the other direction, over a network.

VNC is platform-independent  a VNC viewer on any operating system usually connects to a VNC server on any other operating system. There are clients and servers for almost all GUI operating systems and for Java. Multiple clients may connect to a VNC server at the same time. Popular uses for this technology include remote technical support and accessing files on one's work computer from one's home computer, or vice versa.

VNC traces its roots back to the mid-1990s, when it was developed as a joint Olivetti-Oracle Corp. research effort. AT&T purchased the Olivetti&Oracle Research Lab in 1999 and shut it down a few years later, but some of the developers who created VNC continued to work on it as an open-source software project. In other words, VNC is technology with deep roots and very strong developer support.

As you can see from the description I included above, one of VNC's biggest strengths is its outstanding cross-platform support. On my home network, for example, I have a couple of "headless" Mac and Windows XP boxes that I access using VNC clients installed on other Windows and Linux systems. In each case, these VNC-based servers and clients all have two things in common: They are remarkably easy to install and configure, and once I have them running they rarely trouble me with so much as a hiccup.

If you need to access a PC from outside a local network, then of course security is a much more important consideration. The VNC protocol does not provide any built-in security; as a result, it is very important to understand what security, if any, a particular VNC-based application provides. While I think the free version of RealVNC for use inside a firewalled network, for example, its lack of session-encryption support makes it unsuitable for outside-the-firewall use. (The commercial version of RealVNC, however, does include strong session-encryption support, and it's a great option for many business users.)

Fortunately, another free VNC-based product does provide all the security most users will ever need for true remote-access applications. UltraVNC supports an open-source security plugin that encrypts both your remote-access password authentication and data transfers, and it even supports authentication based on Windows Active Directory user-account settings.

Although UltraNVC provides some other plugins designed to make tasks like firewall port-forwarding unnecessary, I have found that it is still a good idea to be comfortable with basic security-software configuration tasks in order to get the most out of these tools. If that isn't your thing (or if your company's IT guru is too busy to give you a hand), then never fear: There are a lot of great commercial remote-access tools available, such as GoToMyPC, that offer a more user-friendly installation and setup process.