How Zone Alarm works, the free firewall for windows

Zone Alarm, the best freewall for Windows, you can download it from the download page

What is Zone Alarm?

As I explained in the previous article the systems of our machines don't defend us from connecting to internet without the user's knowledge. Zone Alarm protects us such connections and works for Windows.

Setup

After downloading the Zone Alarm installer (which is called something like za_setup.exe) we have to double click it and proceed with the installation. There are two screens we have to pay some attention.

In the first screen we have to say No, thanks if we want the free version (sorry the captures in this article are in Spanish)

Depending how we answer in this screen ZA will decide how to act

How it works

Once installed Zone Alarm, restart the machine, and entering again into Windows a tutorial to learn how it works is offered. If you want to learn its operation follows the tutorial is not very long and is quite enjoyable. Let's go to the main screen of Zone Alarm.

In the Zone Alarm main screen shows how many incoming intrusions detected and which programs are controlled to avoid outgoing connections

This screen does not present much difficulty, simply informs us of the intrusions. Just after installed the Zone Alarm probably will appear a dialog box like this.

Zone Alarm dialog, warns us that the program AVG Network scanner is trying to connect to internet

Each time you activate a program that wants to connect to the internet, whether you have activate it or not (eg, a Trojan), Zone Alarm notice that the program is trying to connect to the internet, in this case, it warns me that the program AVGNSX.exe, which corresponds to AVG Network scanner is trying to connect out. As the AVG Network scanner is a program that I know and who I trust tell Remember this setting and Allow, if you do not activate the option Remember, each time the AVG Network scanner is activated you have to click the Allow button This would be a little bit tedious. So I tell it Remember  so that it will remember and it won't ask again.

In this case, as I know AVG Network scanner, no problem, but it can happen that I don't know about the program activated, for this case we have to click the More Info button and we are redirected to the Zone Alarm website where we can be informed of the intentions of the program. And with this information we can decide if we have to let it connect to the Internet or not.

At first it may be a little tedious watching this dialog appearing every time, but saying Remember and Allow the ZA will ask less until it wouldnt ask anymore.

Program list controlled by Zone Alarm

If we open the zone alarm and click on the Program Control option and in the Programs tab we will see the list of applications that have Internet access or not, the question mark means that ZA are going to ask if the program can connect to the internet or if you have a green check mark means that we have given permission and we trust this application (in this example the AVG Network scanner), at any time you can go to this list to change this permissions list by simply clicking on the mark.

We also see that there are two columns, one says Access and the another Server, this means that there are also applications that connect to the internet to send data, are prepared to receive, such as a P2P like e-mule or Bittorrent that in addition to sending the data they receive data through its own ports. The are acting as a server application.