Microsoft Office Tutorials and References
In Depth Information
Testing Internet Security
3. Click All Service Ports to begin the scan.
4. When viewing the results, make sure that everything is in green or blue.
You do not want any ports to be open for maximum security, which is
indicated with red. Green indicates your computer did not respond at
all, giving your computer a stealth look. Blue indicates your computer
responded that the tested port was closed.
If your test results show any ports that are open, you can find out how to
close those in the “Using a Firewall” section, but first, if you are connected to
an internal network, it is a good idea to test your internal vulnerability. As
I mentioned earlier, it is best to use a software port scanner for testing your
internal vulnerability. For this test, you learn how to use Axence NetTools, a
comprehensive network tools suite with a fast port scanner. To get started, visit
follow these steps to scan your computer’s local ports:
1. After you have downloaded and installed Axence NetTools, start it if it is
not already running. Open the Start screen, type nettools , and press Enter.
2. After NetTools starts, click the Scan Host toolbar option on the icon bar.
3. In the Address box, type localhost .
If you want to scan a different computer, you can type the IP address of
any computer in this box.
4. Set the port range for it to scan. In NetTools you have four options: Services,
Ports (well known), Ports (well known-extended), and Ports (range). For
this example use Ports (range) to scan all possible ports.
Enter 65535 in the end Ports box so that it goes through all possible port
The other selections scan only the more popular ports where known
applications are running. If you want a quicker scan, I recommend using
Ports (well known-extended). Because you want to do a complete scan
here, select Ports (range). The two ports boxes will be enabled.
5. Click Scan next to the Address box and watch the results appear, as shown
in Figure 19-1.
It can take more than an hour to scan all 65,353 ports on your computer,
depending on your hardware. After it is finished, you have a list of all ports
that are open in your computer. You find out how to close these ports later in
the “Using a Firewall” section.