What is a firewall? Does install on Windows 7, 8 or 10? [Full Guide]

12:46 am November 17, 201613761QUICK GUIDE

before that Windows does not have a built-in firewall and before the democratization of the internet box, which are also equipped with a firewall, users hastened to install firewall software on Windows , the latter being the first line of defense for a user in the face of the threats from the Internet . But today, fewer and fewer users concerned with this component essential to the computer security on the Internet. A wrong or right? Is still needed to install a software Firewall on Windows to increase the security of my computer or is it today totally useless? It is to these questions that this article will attempt to answer today! But first, let’s start with a brief presentation of the firewall (or ‘firewall’ in English) as well as threats against which it protects you.

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when you are connected to the Internet, your computer may at any time be victim of external intrusions.

why pirate computer would want to tackle me? I’m nobody!

don’t be so hard on yourself 😉 more seriously, we have to finish with the cliché of the pirate who taps on the keyboard of your PC trying to take control of the computer of Ms. Michu and thus steal her photos to vacation in La Baule. Although it is always possible, the motivations of these pirates are diverse and varied:

  • in a professional setting: fly confidential information such as trade secrets or intellectual property;
  • in a private setting: steal the personal computer as photos, emails, of intimate conversations in order to swindle the victim (back to the cases of Ms. Michu);
  • retrieving data bank ;
  • recover the accounts and passwords used to connect to various services (Facebook, Amazon…);
  • use the system of the user as ‘bounce’ for an attack (instead of directly using my machine, the hacker uses your to launch attacks, allowing it to remain hidden);
  • use the resources of the system of the user as the processing power of its processor, the bandwidth of the network connection…

you do understand now that even if you are not necessarily interested hacker, it isn’t the same for your system and all the data that it contains 🙂

how the pirate is y it takes for attack my computer ? How can he find me? My computer melts into a mass of billions of machines!

unless you are a public figure or a manager of a company of the CAC40, there are in fact very little chance that a hacker attack frontally your machine. But you are far away because the pirate will use more vicious methods in order to infect your computer , and take control:

  • Via the “Exploit Kits” : infection is by visiting the page of a website hacked or containing a malicious advertising that will download a “Exploit Kit”. a tool that exploits vulnerabilities in your system to infect with malware. This “Exploit Kit” is designed by the hacker to perform at least 3 basic actions:
    1. analyze vulnerabilities system
    2. exploit vulnerabilities he discovered in downloading malicious code in your system
    3. run the malicious code on your system (which means that it is able to install malware on your machine)

    “Exploit Kits” operate so security vulnerabilities possible browser or programs that a Web site can invoke via the browser (Adobe Reader, Java Runtime Environment, Adobe Flash Player…) in order to download and execute the malicious file on your machine. That’s why it is important to maintain its system as well as its software updated . Note that it is visually impossible to distinguish a pirate site of a healthy web site, download the malicious file is done discreetly.

  • via an attachment to an e-mail (spam) which will also exploit a vulnerability of your system and run malicious code.
  • via the installation of a rogue (rogue security software) or a fake (false copy of software that looks like two drops of water to the original software – fake Chrome, fake CCleaner, etc.) which will come infect your machine .
  • via programs analysing all communication ports all the IP addresses of the world, looking for potential security vulnerabilities.

what happens when my computer is infected ?

once infected, your computer will become one machine zombie, more often that you know for. A zombie machine is a machine without the knowledge of my user-controlled a cybercriminal, who uses it to malicious purposes, in order for example to attack other machines by hiding my true identity or to get all your personal information . The infection is usually silent , the purpose of the pirate being that you don’t you doubted nothing while its malware Act.


it is here that the firewall will play a role to ensure the safety of your PC!

the firewall protects your PC by blocking suspicious connection attempts

the firewall is one material or a application that allows to filter connections outbound and inbound that are made from and to your computer. The firewall is located between the user and its applications and on the other the internet connection.

Firewall analyzes network traffic entering in order to verify that it contains no data on black list. Following the generation of the firewall or its precise role, one can classify firewalls into different categories. The best-known firewall categories are:

  • stateless Firewall ( stateless firewall ). It is the oldest device filtering network, introduced on routers (a device that connects your computer to the Internet). It is this type of firewall are equipped with the internet box (Freebox, Livebox, etc.). stateless firewall looks at each connection independently from each other and compares them to a list of pre-established rules . Under these rules, the firewall will allow or block the current connection . You can create your own rules on communication ports. For example, you can create a rule that allows connections to port 20 and 21 If you have a FTP server on your machine. Thus, anyone can connect to your FTP server.

    Inbound connections allowed on different ports of communication on the Freebox Server

  • personal firewall is software installed on the personal computer of a user , which controls communications inbound and outbound, authorizing or refusing them according to implementation on the system security policy. The personal firewalls is interactive , that is, he seeks the user as soon as a new connection is detected by asking him to do (allow or block the connection). It only protects the machine on which it is installed. my goal is to combat computer viruses and spyware and thus of protect the PC of the user .

    Connections inbound and outbound a PC Windows visible with the firewall GlassWire

how the Firewall works to defend my PC against malware?

, firewall refuses and basic banned everything that for not been explicitly authorized . As a result, he defends computers against viruses, worms, Trojans and attacks of brute force hacking. So, unless you allow a dangerous network connection, you’re safe 🙂

reminder, network traffic is composed of incoming connections (connections who want to access your machine) and outbound connections (connections issued from your machine to another network – e.g.: Internet). By allowing to control connections inbound and outbound, the firewall helps prevent users or malware to access your computer (incoming connections) and your computer to send the malicious software to other computers or your personal information on servers of the pirate (outgoing connections).

the firewall personal, essential to improve the security of its PC

you don’t maybe not but you are already protected by a firewall , or even two firewalls ! Your internet box and Windows 🙂 Windows for a firewall built-in since Windows XP SP2, called “Windows Firewall”. And as your internet box office router, it also for a built-in firewall.

super! But what the Windows Firewall is effective ?

Yes, it is sufficient for the majority of users who have a prudent behaviour on the Internet. But be careful: it filters only traffic entering and not coming out ! It protects so as intrusion from the Internet exploiting remote vulnerabilities of security of your system, as for example of the Conficker worm appeared in late November 2008, which exploited a flaw in the Windows Server service.

Windows Firewall protects not PC exploits on hacked web sites. The exploits may indeed make a outbound connection to download and run an infection which is similar on your system. Windows Firewall does protect your PC of the Trojan.Downloader, those applications that download and install Trojan horses on your computer with outbound connections.

good OK but with the firewall of my internet box , I have to be doubly protected no?

a router (such as your internet box) integrates a firewall which protects the local network computers that are connected. The router only allows connections from the local network. In other words, the firewall of the router will allow outbound connections from a computer on the local network and block all incoming connections from the Internet. If you followed… we are facing the same problem as with the Windows Firewall: you will be protected from worms exploiting remote vulnerabilities in your system (incoming connections) but not other forms of malware (outgoing connections).

this is why we should install a personal firewall in Windows to increase the security of your machine. in addition to blocking incoming connections, personal firewall will block all outbound connections except those that you have explicitly authorized.

when a program wants to connect incoming or outgoing, the firewall will immediately stop the connection and ask the action . You have the choice between:

  • allow once the connection;
  • connect all the time;
  • block once the connection;
  • block while the connection.

allowing to block outbound connections, you will for example be protected exploits as we saw earlier.

you are spoilt for choice for install a personal firewall on your PC. you can find firewalls free, the pay and security all-in-one solutions that incorporate antivirus and firewall.

Yes, you need to install a firewall on your PC!

do I really need to install the firewall of a third-party editor on my PC?

Yes, you need! is a component that is for me very important Although it is not necessary . With what is happening on the Internet these days, it is too risky to surf without your outbound connections to be filtered, unless you know exactly what you’re doing or have a prudent behaviour on the Internet.

any computer should have and be behind a firewall.

the firewall is always security solution n ° 1 for a computer network, although nowadays it for lost in importance as and as communications switch (non-secure communication protocol) HTTP to SSL/TLS, bypassing any filtering. You can see for yourself by visiting the Google home page, the communication is now done via the HTTPS protocol (with S for Secured, or ‘secured’ in the language of Molière) which is the secure variant of HTTP by the use of the SSL/TLS protocols. Nevertheless, dangerous websites will always be blocked, there is that the exchanges between you and secure sites that are invisible.

Finally, be aware that firewalls approach more and more the detection systems intrusion or IDS (Intrusion Detection System), mechanism to identify anomalous or suspicious activity on your computer. If an application requests access to an important system file, the firewall can alert you and ask you to allow or block the application access to this component. Additional protection! 🙂

in the next few days, I would suggest an article suggesting the firewalls preferred on Windows 😉