If you have several home or small office PCs connected to the Internet, then you need to know about Network Scanners and how they work together with your firewall to keep the bad guys out and the data in.

Hackers have software which runs automatically and lets them effortlessly try to break into all computers on the Internet. The software that they use does this by generating every possible address combination that could be assigned to an Internet-connected computer and then trying to gain access to that computer via all of its connected ports.

Once they get inside one of the PCs on your network they are inside all of them. At that point all of your data, including business records, documents, email, financial transactions, and anything else stored on your network is open to them. You can guess what happens next.

Network intrusion is not some worst case scenario. It happens every minute of the day somewhere in the world. With thousands of hackers running this same software, it's only a matter of time until one of them starts probing your home or business network. What will they discover when they do?

Recent attacks, such as the "BackOrific", resulted in millions of dollars of damage and lost data. This particularly nasty attack was capable of the following

Executing any application on the target computer.

Logging keystrokes from the target computer.

Restarting the target computer.

Locking the target computer.

Viewing the contents of any file on the target computer.

Transferring files to and from the target computer.

Displaying the screen saver password of the current user of the target computer.

All of this was happening without the computer users ever being aware.

The only way to stay on top of these attacks is to lock the doors that these hackers use to gain entry. And for that, you need a network security scanner.

While it sounds so high-tech and ominous, a network security scanner is really very simple to operate. Just install the software, give it the range of IP addresses that your network uses, and let it run. It will produce a report that shows all of the vulnerabilities and policy discrepancies that it finds as well as suggested ways to fix them.

These network scanners use internal databases of hundreds of known vulnerabilities and internal security issues. As new risks and exploits are discovered the database is updated by the vendor.

The scanner makes its way through your network just like a hacker would. It explores every IP address, device, and port that it encounters to see if it can exploit it in any way. It also checks for poor security policies such as disk and file sharing access that is not password protected, default manufacturer's passwords and hidden "back door" passwords that haven't been changed, server and router misconfigurations, and out-of-date server software that may be open to known attacks that you could prevent simply by upgrading.

This is a low-cost and highly effective alternative to hiring a network security consultant who will just end up running the same type of software anyway but charge you more.

While the software itself is very sophisticated, the reports are clear and concise. You don't have to be Head Geek to read them and, even if you do not have the technical knowledge to do the repairs yourself, you can hand the report to any capable IT manager or consultant and have them make the fixes.

Here is the scanning software that I recommend. They have a free version and an evaluation version. If you purchase their registered version it will include database updates:

http://www.gfi.com/lanselm/

It's only a matter of time until your network is probed. Unless you probed it first, and patched the holes, you could be in for a business-wrecking surprise.