What is a firewall: the answer to a question

If you are asking about what a firewall is, you probably have a problem setting it up. In other words, it is a firewall, or a kind of bastion, the main task of which is to view the headers of all packets transmitted over the network interface of your computer. According to the established rules, it performs actions on these packages.

And the firewall can stand both on the protection of a certain home computer, and the entire network. Configuring the firewall on the network occurs on a so-called gateway computer that provides other users access to the Internet. In this article, we will try to understand what a firewall is, using the example of a single computer and Windows 7.

The primary task of the firewall is to protect your computer from various network attacks, worms, limit the performance of malicious programs, and so on. Data in the network is transmitted in packets, not entirely. This is done to ensure that network traffic is distributed evenly. In order to answer the question about what a firewall is, you also need to figure out what the package consists of.

The package is divided into two parts - the body and the header (the service part and the data areas, respectively). If the header contains the service data (the port of the sender and the recipient, its address, the size of the transmitted data, etc.), then the data itself (part of a music file or movie, e-mail message, etc.)

If the firewall is enabled, in the process it checks the headers of all packets that are received or sent through the network interface. A set of rules is set by the system administrator, i.e. you. For example, you can disable all incoming connections, and no one can connect to your laptop. What is a firewall? This is a kind of wall between your computer and the network. Using it, you can also prohibit unwanted programs or use a specific port (for example, by closing port 5190, you will disable ICQ).

Many people today are interested in the question of whether to disable the firewall on Windows 7. After all, in Windows XP only one hour spent on the Internet without the firewall turned on, almost 100% meant infection with a virus or malicious program. When answering a question about what a firewall is, it's worth noting that it is in Windows 7 that it copes with the task perfectly. In fact, it can easily replace such powerful programs as Kaspersky Internet Security: for a few months of work on my computer, by checking the system DrWeb and Curelt programs did not detect a single virus. And the flexibility of configuration and clear navigation in the Windows 7 firewall is another plus. If properly configured, it can easily replace paid third-party firewalls. And if it still does not suit you, then you can download an alternative, for example, Outpost Security Suite Pro.

If you do not have third-party firewalls, then it's extremely important not to disconnect the native version, relying only on the router or hardware firewall between the Internet and your PC. Otherwise, you risk infecting the system with viruses, and very quickly!