What is a firewall and how to use it. What is a firewall in Windows and how to configure it? Firewall protection levels

(translated from English firewall- can be designated as a fire wall, fire partition), otherwise called firewall is a special application that allows only those connections that are permitted by the owner of the computer, and thus protects your computer from outside interference.

By the way, the firewall keeps under control not only incoming connections, but also outgoing ones. That is, even if a virus somehow got onto your computer and tries to “leak” your personal information to someone on the Internet, it will be detected, at least attempts to “leak” information will not escape the attention of the program.

Now no one will be able to get into your computer and extract your information. Uncontrolled traffic leaks have been stopped.

The best firewalls

Now let's see what the most are:

#1

Comodo Firewall - interface

Today it is one of the most powerful firewalls, which allows you to block the loading of advertising and active content of web pages. It also monitors suspicious emails. These firewall capabilities are implemented using special algorithms that filter network traffic and keep open connections under control.

In addition, these algorithms are capable of detecting and prohibiting any suspicious actions that are carried out both on your computer and outside it, on approaches.

#2

ZoneAlarm Free Firewall - interface

Another good firewall, which has the ability, unusual for firewalls, to protect your personal computer from various network dangers - the ubiquitous hackers, spyware and many others. How he does it? Zone Alarm Firewall prevents even the most sophisticated hackers from accessing your protected computer, making it seemingly invisible to anyone on the Internet.

It is also capable of blocking the possible sending of any information without permission, and also protects all programs and the main operating system of the “protected” PC from any kind of malicious programs.

#3

Windows Firewall Control - interface

This is a fairly convenient firewall that can control all ports and Internet traffic. In addition, it can block potentially dangerous web pages and advertising pop-ups (so-called pop-ups). Installing the program will not be difficult even for a novice user.

Other firewalls

This is not a complete list of existing firewalls; their selection is quite large:

• Kerio Personal Firewall– the most “advanced”;
• Lavasoft Personal Firewall– simpler, but no less effective;
• Tiny Firewall Pro– best protection for small networks;
• Webroot Desktop Firewall and etc.

The essence of the problem

When they talk about computer security, most users think about fighting malicious computer viruses. But viruses- this is not the only problem awaiting a PC user on the Internet.

Perhaps you have noticed that, even if you have anti-virus software installed on your PC with updated databases, you very often lose the necessary files, although it behaves calmly and does not react in any way? Or another case - the Internet limit that you expected to use for a whole month suddenly melted away in a few days? Have you encountered this? Well, consider yourself lucky so far. But there are also those who are not so lucky...

So, why do these strange things happen? Actually the explanation is simple. But first, a little clarification. As you know, every PC connected to the Internet has a unique IP address, a kind of telephone number made up of 4 standard numbers, each of which can be from 0 to 255. Your computer needs an IP address to communicate with any other computer on the Internet.

Imagine a situation where several programs from your computer must interact with the Internet at the same time, sending and receiving some information. How do they determine where whose data is, why are they not confused? For these purposes, in order to separate information flows and deliver it to the recipient, each PC is equipped with so-called "ports", the number of which is more than 65 thousand. They allow a large number of programs to simultaneously work with the Internet.

Suddenly one day you notice that a certain port N is showing some strange activity, it looks like someone unknown is trying to take over your computer. Maybe you told one of your friends your passwords, and now he is hacking your machine, trying to prank you? What if these are competitors of your company who somehow found out your passwords, and now they find out all your secrets, including financial ones? Everything is lost? What to do???

First of all, you just need to calm down. Do you remember the most popular questions in our country (and not only in ours)? Yes, yes, yes - “What to do?” and “Who is to blame?” You will find the answer to the second question yourself, but you will find the answers to the first question in this article. In order to avoid such dangerous situations, it is necessary to ban your computer from communicating on all ports that cause suspicion, that is, communication will only be with those with whom we ourselves want. The perfect solution, isn't it? And this can be done with special software called firewall.

Bottom line

If your computer has a standard operating system installed, for example, a fairly modern Windows XP with SP2 service pack, then you already have a built-in firewall.

Well, you've learned about another way to protect your PC. Remember - you shouldn’t skimp on computer security; restoring everything will be much more expensive, both in money and time.

Many users have more than once found such a definition as “firewall” in the help of their computer, on forums, or heard from friends. And you probably wondered - what is a “firewall”? Where does it come from on a computer, what functions does it perform, and, in the end, why is it needed?

A firewall is a set of software network filters that filters network packets entering and leaving the PC. He controls it all according to the rules specified in the program.

Firewall has another definition, which all users have probably heard - firewall (German - “fire wall”). This is a so-called firewall that allows you to protect your computer from unwanted incoming connections. The principle of operation is simple - the firewall program monitors all network connections (both incoming and outgoing), then checks them against a given list. If the connection is not in the list (especially if it is prohibited), then the firewall blocks this connection and displays a warning on the screen that this *IP*port* connection is blocked. The user has the right to change the list of allowed connections, add and remove permissions for the network connection of certain programs.

In this article, we will not consider corporate firewalls with their various tracking methods and complex operating algorithms. I will talk about personal firewalls that are installed on the computer of an ordinary user. The firewalls below are capable of protecting only the PC on which it is installed from unwanted network connections.

What firewalls can be used? There are many such programs, but in this article I will highlight only the most popular and reliable programs. So, let's go through the list:

Agnitum Outpost Security Suite Pro 7.52 (http://www.agnitum.ru/products/security-suite/index.php) - firewall from a well-known Russian company. Peculiarities:

• Fast virus detection and removal scanner.

  A “two-way” firewall protects against both internal and external unwanted connections.

  Interactive user help system.

Avast! Internet Security 7 (http://www.avast.com/ru-ru/internet-security) is an equally well-known Czech antivirus with a good built-in firewall. Among the features:

• Blocking all unwanted connections

  Checking all connections against your own database.

Comodo Internet Security 2012 (http://www.comodo.com/home/internet-security) is an interesting American firewall, which, like previous firewalls, comes bundled with antivirus software.

• High-quality blocking of unwanted connections.

  Free to use.

Jetico Personal Firewall 2.1 (http://www.jetico.com/download/) is a Finnish firewall that does a good job of protecting your computer from unwanted attacks. How is it different from competitors?

• Three-level filtering system - monitoring network packets, filtering the work of network applications and filtering the actions of all user processes.

  Convenient control of the connection filtering process.

Kaspersky Internet Security 2012 (http://www.kaspersky.ru/internet-security) - we almost forgot the world-famous product of Kaspersky Lab. This antivirus software with a built-in firewall has many advantages, including:

• The most complete and effective protection of your computer from external and internal attacks.

  Convenient firewall management.

  Ability to fine-tune network filter parameters.

As you can see, almost all firewalls come with anti-virus software. This is convenient, because all modules are in one program and provide comprehensive protection for your PC.

A firewall is not a panacea for all virus attacks. What should you do to make the most of this software? You just need to carefully read all firewall messages, allow access only to those programs that the user really knows and trusts, know exactly the ports that trusted programs use and not allow access through others, and always act on the principle “it’s better not to take risks - ban again rather than allow and be upset by the consequences.” And then the firewall will be able to provide maximum benefit to the person using it.

Like

Many Internet users have little understanding of what is a firewall, what are its main functions, what is it used for. In addition, you can often hear the question “isn’t antivirus enough?” If earlier this statement was completely incorrect, today many antiviruses already include some firewall functions. However, there is a difference, and a significant one. This will be the topic of this article.

Note: I’ll say right away that the article is primarily intended for beginners and ordinary users, and therefore does not contain a complete technical presentation.

Firewall is a software or hardware complex that monitors all packets passing through the network in accordance with specified rules. Typically, a firewall controls one or more layers of the OSI model. Its main tasks are to protect the internal network or an individual computer from possible external threats, as well as to prevent the spread of malware and information leakage from the computer to the network. Along with the name firewall, it is also called a firewall or firewall.

Note: The OSI model is a standard that today divides network protocols into 7 layers. The word “packet” means a unit of information transmitted over a network in the form of a complete message (may include parts of a message from higher-level protocols).

The term firewall itself comes from the expression “wall of fire,” which is an ordinary brick wall. The purpose of such a wall is to prevent the spread of fire during fires, since the brick does not burn. Typically, such walls can be found, for example, on the roofs of houses at the junction between two entrances.

Note: By the way, this is why in images the firewall is often represented as a brick wall, as in the picture below.

In relation to information technology, a firewall is intended for the same function - to limit the spread of malware. It is important to understand that we are talking not only about preventing a virus from the outside from getting onto your computer, but also about preventing viruses from your computer or local network from getting onto the Internet. For example, if you already have a Trojan program with a network worm, then it will not be able to send data or infect other computers.

What is a firewall used for and how does it differ from antivirus filtering? Antivirus tools usually monitor only part of the network activity, namely web pages and email (in both cases, mainly files). But the networking possibilities are not limited to this. There are many other protocols and opportunities for spreading malware. To control them you need a firewall. It’s worth knowing that advanced firewalls have a fairly flexible system of settings and, for example, allow you to set rules up to limiting access for individual programs, and also provide a lot of useful functions, such as filtering websites by content.

Note: If you are interested, here is a selection of the best free firewalls that will improve the security level of your operating system.

Such capabilities often turn out to be very useful not only for the purpose of fighting viruses and network worms. For example, today there are more and more programs that “at every sneeze and squeak” try to get onto the Internet and send or download something, without your knowledge. When it comes to online programs, such behavior may be justified, but when it comes to a small program for local use, such actions raise reasonable suspicions.

Note: It is worth understanding that antivirus programs usually do not detect such actions.

In general, a firewall is used in conjunction with an antivirus tool as an additional tool to provide a more flexible and reliable level of protection for your computer’s network activity and transmitted data.

firewall- from English “Fiery = fire, wall= wall". Synonym words: Firewall, firewall, firewall, firewall- formed by transcription of the English term firewall. These are hardware units or programs that monitor and filter network packets ( internet traffic) according to specified rules by the administrator/user.

Firewall(from German Brandmauer) - which is an analogue of the English word firewall. Original meaning (a wall that separates adjacent buildings, protecting against the spread of fire).

Any " firewall», « firewall"or otherwise called " firewall“[I would like to punch the person who came up with such a combination of letters in the face] is responsible for filtering network traffic from unwanted, critical operations at a low level. Both at the level of network cards or network protocols, and at a high level, for example, setting access rights for applications. All functions come down mainly to permission or prohibition " incoming" or " outgoing» information packages. That is, before sending or receiving a network packet, the Firewall checks for correctness and security.

« Incoming packages" - these are packets that come to your computer from any computer.

« Outgoing packets" are packets that originate from your computer to another address.

For example, if you allow a program to work, and by default it is always allowed to work with network packets, then accordingly network packets will be passed back and forth without hindrance. But if network packets come from an application that you have not given permission to operate, then the connection will be automatically blocked. Well, accordingly, if any application tries to “ go to your computer"for the first time, then Firewall asks you, they say, " But what should we do with this pepper?“Here it’s up to you to decide whether to allow this application or network traffic to work or not.

Which Firewall to install

There are both free and commercial products (Firewall) on the Internet, but we will talk about them in a separate article. See the best below.

Firewall protection levels

Typically, there are 3 types of protection levels in a normal Firewall:

Weak level of protection and filtering of network traffic. With this mode, almost all traffic is allowed, with the exception of very suspicious packets, which, as a rule, have already been identified in advance as attacks by the enemy.

Medium level of protection and filtering of network traffic. Here, as a rule, all ports are blocked, but many well-known ports are also allowed, through which, by default, supposedly no suspicious traffic can pass, and many applications are allowed to work, which by default do not cause suspicion of potential danger. By default, Internet Explorer does not cause danger, which, as practice shows, is often not the case. At this link, I already told you what is wrong with browsers and holes in their security system.

High level of protection and filtering of network traffic- absolutely everything is blocked, regardless of whether the connection is secure or not. Everything will have to be resolved manually. For beginners, this mode is absolutely not suitable, because you need to be very obsessed with computers to understand what needs to be allowed and what to prohibit. Because with this mode, in the first minute you will be asked at least hundreds of questions.

Firewall also has some other useful properties, for example, identifying and warning about possible upcoming attacks. That is, protection from so-called “scanner” programs.

Scanner programs- these are programs that on a remote computer, [can also on a local one] in turn, sort through all network ports in order, from 1 to 65532, or selectively scan for “ closedness"and security are those that an attacker needs.

Firewall, firewall, firewall - which one to choose?

How to choose a Firewall? Here, first of all, there is a question about the professionalism and experience of the user. Today, one of the leaders in this area can be safely called OutPost. But it is clearly not suitable for a novice user, due to the abundance of settings. Since it’s easy to go through the settings and click on options, an ordinary user can block the entire computer and network traffic purely. Therefore, the Firewall, first of all, should be easy to use and configure. I won’t talk about the interface and controls; this is a topic for a separate program and, as a rule, there is a lot of information posted on official websites than I can describe here. Therefore, we read about the interface and management on the native sites of well-known firewalls.

The irreplaceable good qualities of Firewall are:

• self-learning ability, so that he can analyze the traffic himself and intuitively suggest what is wrong on the network;
• automatic updating of self-changes and updating of virus attack signatures;
• strict implementation of the prescribed rules, that is, if you need to completely close access to 21 ports, then it must close 21 ports without any exceptions for any programs. Since such a rule is often superficially implemented.

Based on popularity, prevalence and a certain kind of respect for professionalism, I offer my Firewall:

• Panda Firewall is strong, but not everyone, even a semi-pro, will be able to configure it correctly. As Zhvanetsky used to say, “ one wrong move and you're a father", that is, you can easily block the computer completely, right down to the spine.
• Outpost Firewall is strong, but not at all suitable for beginners;
• Kaspersky Firewall - public transport
• Norton Firewall - public transport
• McAfee is the cheapest free solution. In my experience, it is either there or not. That is, the memory does not load, but there is no effect.

So, I briefly introduced you to the concept of Firewall. It is worth noting that today (April 2010), only Panda Software and Kaspersky Antivirus combine two concepts like a firewall. The rest are independent units. And using Firewall separately doesn’t make much sense because its efficiency tends to 0. I’ll try to explain with an example. There are two doors to enter. One door is protected by , and the other by Firewall. Therefore, if one is not covered, is there any point in protecting the other? That is, I strongly recommend using both an antivirus and a firewall.

Let's look at the actions of this sweet couple using one example of an invasion. Suppose a completely new virus, a Trojan, has come to our computer and bloodthirstyly wants to steal our keys to the WebMoney payment system, where the money is. The first line of defense screwed up and missed the virus because it could not detect the corresponding signature for the new virus in its databases, and therefore could not recognize the threat. Suppose the virus has collected all the information it needs, its goal, of course, is to transfer everything it needs to its owner. Naturally, in 99% of cases, all information is now transmitted via . The program tries to transmit information, but here our Firewall comes into play. It’s clear that if he doesn’t know this program, and he doesn’t have the rule of letting everyone through, then he’ll ask, “Who are you?” Here is a Trojan, “tyr myrk, yes, I’m here, from Gagarin Street, the local is shorter than me,” and Firewall “wait now, I’ll ask the master. Hey sir, there's some suspicious pepper here trying to take some rubbish out of your kingdom on a cart. Of course you must answer No and try to figure out where the legs grow from. And take all measures to destroy the foreign body in our beloved computer body.

Bottom line

As practice shows, it is not so easy to recover from a new and unknown infection that has visited your computer. If you are not a high-level Internet user, then I recommend that you urgently update your antivirus. If it doesn't find anything, try another antivirus, since not all antiviruses are equally useful now. Well, I think that in this article I more than adequately told what Firewall is and what it is for.

Good luck and safe masturbation on the Internet.

Any operating system must have at least some kind of protection. Windows has two security features: a firewall and Windows Defender. The very concept of "firewall" has several meanings, but in this material a variant of the firewall will be analyzed.

What is a firewall?

Firewall (firewall) - is a firewall in the Windows system that prevents unauthorized access to a computer from the Internet and local networks, as well as prohibiting or allowing applications to connect to the network.

In simple words, a firewall is a wall or a closed door that only opens to those who are allowed to. In Windows, restrictions are usually placed on software that communicates with the Internet. Now we have understood the concept of a “firewall,” but how to configure it correctly to provide protection for your computer?

How to set up a firewall (firewall) on Windows 10?

In offices, this is done by the system administrator, so it would be a good idea to have the skills to configure security software. At home, anyone can change the computer settings as they want, but within reason.

Setting up a firewall after installing Windows 10 is very simple. First, you need to figure out how to enable or disable protection, since problems with the firewall cause various critical errors that can be fixed by simply disabling or enabling the protective function.

One way to access the firewall settings is as follows:

• We use the following key combination on the keyboard: Win + I. Then go to the “Updates and Security” section;


• Go to the “Windows Defender” subsection on the left;


• Click on the button on the right “Open Windows Defender Security Center”;


• In the open window, select the “Firewall and network security” option.

There is a new interface here where the settings are a bit confusing for a newbie. If you don’t like the layout of the functions, you can, of course, return to the old, familiar interface, as shown in Windows 7 and 8. To do this, click on the search on the taskbar and enter “Firewall”, selecting the result.

When you are in the firewall window, in the tenth version of the system you can see two items - “Private network” and “Public network”. Both of these options contain options to disable the firewall for the connected network. Here you can block all incoming connections by checking the box.

To allow programs to connect to the network through a firewall, you need to find the “Allow applications through a firewall” item below. A window will open where changes to the parameters will be made after clicking the “Change parameters” button.

If the checkbox is checked, software exchange via the network is allowed. Typically, permissions are set only for Microsoft applications. If there are problems with the firewall, there is an option to resolve them " Troubleshoot network connection". Use it whenever possible.

By going to the “Notification Settings” section, you can see options that allow you to display notifications about blocked programs in the system. If you have configured the settings incorrectly, you can “Restore Defaults”. This option is on the main screen.

How to add a program to an exception in the firewall?

1. In the main firewall window, go to “Firewall notification settings”;


2. Click on the “Virus and threat protection settings” option;


3. Go to the “Exceptions” section and click on the button in the “Adding and removing exceptions” item;


4. Now click the “Add exception” button and select the element that is not malicious in your opinion. You can add files, entire folders, specific file types, and processes.

Additional firewall features

You can enable or disable the following features in Anti-grayware and anti-malware settings:

• Real-time protection - if you disable this protection, it may lead to the active operation of those programs that have been blocked.


• Cloud protection – allows you to protect data in the cloud.


• Automatic sending of samples – data about detected malicious components is sent to Microsoft servers.

The remaining settings have already been discussed above.

Setting up a firewall on Windows 7 and 8

If you have outdated versions of operating systems, setting up the firewall is a little different:

1. Open the firewall from Control Panel.


2. The necessary settings are located on the left side of the window, and access to them is faster than in Windows 10.


3. To enable the firewall, click on the “Turn Windows Firewall on or off” option button. Immediately after this, check the “Enable...” checkboxes.


4. You can also immediately reset settings to default, enable application communication in the firewall, and configure notifications.

Firewall Security Rules

In the window on the left, go to the "Advanced Options" option. A window will immediately open where you can configure rules for incoming and outgoing connections for applications.