A firewall is a barrier that prevents unauthorized access to computer networks. Used to protect a personal computer and network perimeter. The firewall controls the traffic passing in accordance with the rules specified in the firewall settings.
Network traffic filtering devices appeared in the late 80s. Data filtering was carried out in hardware, for which routers were used. Traffic blocking software appeared much later. One of the reasons for the emergence was the spread of viruses that used the absence of firewalls on computers in their attacks.
Firewall features
The firewall has three commands for working with packages:
- prohibit (deny);
- allow;
- reject.
Denny implies a ban on processing the packet, allow allows processing, reject discards the packet, and the sender is informed that the service is unavailable. During the deny operation, the packet is also dropped, but the sender is not aware of the unavailability of the service.
In order to find out what a firewall is, you need to understand what it does. The main function of the firewall is blocking sites. Used to analyze incoming and outgoing network traffic. This is ensured by the fact that the Firewall is between the network and the computer. It is configured to block certain sites, allows you to keep a log of suspicious network activity. Firewall rules and exceptions are set in the settings, they will prohibit and allow certain types of traffic. For example, you can only allow incoming connections for a specific IP, while other requests will be rejected.
There are two ways to handle traffic. One of them works on this principle. That which is forbidden is not forbidden, and therefore permitted. Another - prohibits everything that is not explicitly permitted. The second method guarantees greater security, because it prohibits all traffic if it is not allowed by the established rules. In this case, the first principle imposes an additional burden on the administrator.
Benefits
The firewall provides accurate identification of the application regardless of the ports used, it determines the user regardless of location. It protects against exploits for known vulnerabilities, has a simple graphical interface if a software solution is proposed. It has multi-gigabyte performance, it has low delays even when all services are turned on.
disadvantages
Manufacturers suffer from the fact that they cannot provide a sufficient set of functional capabilities and provide full protection. Many firewalls still use the old rules, but modern applications already use non-standard ports, thereby easily bypassing the security policy of the traditional firewall.
Additional software is quite expensive. These include URL filtering, IPS, antivirus protection, etc. In addition, a security policy inconsistency occurs, which does not solve the problem of monitoring and controlling application traffic.
The firewall only filters traffic that it understands. Otherwise, it is inefficient and knows how to work with unrecognized information. Some protocols use cryptography and hide content.
Hardware firewall
What is a hardware type firewall? This is a separate device that performs the functions of protecting your computer and network. Often used to protect not a single personal computer, but the entire network at once.
This type of firewall has the following advantages:
- Easy to deploy use. Connecting a firewall and configuring it is very fast.
- It is characterized by low power consumption, has a modest size.
- High performance due to the limited number of functions performed. There are no third-party services running on it.
- Comparing the software and hardware options, it becomes obvious that the latter is more reliable. This, in turn, is due to the fact that it does not run third-party processes.
- Functions depend on the built-in packages, firmware.
Software firewall
What is a software type firewall? This is appropriate software, it performs the same functions as a hardware firewall. It is installed on every computer on the network.
Benefits:
- Low cost. Buying a software firewall is much cheaper than hardware.
- Network protection from the inside. Some threats can be committed from any internal computers. For example, from the machine of an employee dissatisfied with the company. The program provides effective protection in just such cases. Of course, a separate device also copes with similar problems, but for this it would have to be used for each computer. It is very expensive and irrational.
- A large company has many departments: accounting, finance, IT. They do not need to interact with each other, to differentiate, they resort to the creation of several subnets. With a built-in firewall with ISPD demarcation function, this task can be facilitated. In a matter of minutes, the router is configured as required by a separate situation.
- Easy to deploy firewall and configure routing. These actions are performed through a graphical interface, implemented with a few clicks.
- Software typically has a lot more features than hardware counterparts. Some software solutions allow you to balance the load, provide IDS / IPS.
Configure Server Firewall
To work correctly, you need to configure it correctly: add exceptions, open ports. In the Windows 10 firewall, it looks like this:
- open the menu item "Allow interaction";
- go to the submenu "Firewall";
- to manage ports, go to the menu "Firewall in Advanced Security";
- a section with rules appears, on the right side of the screen there is a button for setting new rules - click on it;
- in the appeared “Wizard” for assigning rules, you need to set the pointer on the item “For port”;
- TCP or UDP protocol is indicated;
- local ports are determined, their numbers are indicated.
Disabling Firewall
When using antiviruses with a built-in firewall, you need to disable a separate firewall. To test the connection to any services, it also becomes necessary to include a barrier. To disable the Windows 10 version 10 firewall, you must perform the following list of actions:
- in the "Control Panel" you need to go to the menu item responsible for the firewall;
- determine the protection status by the corresponding icon;
- open the menu item "Turning Windows Firewall On or Off";
- in the window that appears, tick the desired item in accordance with the situation.
Disabling any firewall looks the same as in the case under consideration.
Popular firewalls
When it became clear what a firewall was, it remained to deal with popular software solutions. One of the common free firewalls is Comodo Internet Security. This is a combination of antivirus, personal firewall, Comodo Defense protection module. It is a multi-level protection tool, detects spyware, infections, searches for and removes rootkits, blocks the launch of malware.
Firewall Control Win is used to change settings. Provides quick access to system firewall settings, gives full access regardless of account type, imports, exports, restores established Windows rules, protects against unauthorized removal.
Android Firewall provides strong protection for your mobile device or tablet. With it, you can create white and black lists, set passwords, scripts, manage notifications.
Norton 360 Antivirus with integrated Firewall effectively protects against all kinds of virus threats. It has a powerful scanner, e-mail control module, provides automatic defragmentation, safe cleaning of hard disk partitions.