What is a Firewall?

What is a Firewall?

Firewall, which is referred to as ‘Security Wall’ in our language, is a security set designed to protect information systems from malicious software and individuals. Its working principle involves controlling the incoming and outgoing traffic on a network, detecting harmful situations using specific filters, and preventing them from entering the network. The rules of these filters can be predetermined by users or automatically planned by the system. This minimizes network threats.

On the other hand, firewalls are responsible for monitoring network traffic. If it detects any access from outside the defined network systems, it notifies the user and cuts off the access. It operates based on the concept of a ‘White List,’ meaning that all ports, networks, and processes used before the firewall is implemented are listed, and any process observed outside this list is automatically blocked.

Currently, there are two types of firewalls widely used by systems. The first one is the Software Firewall, while the other is the Hardware Firewall. So, what are their features? Here are the details…

Software Firewall: It is installed within the operating system and operates without requiring any hardware support. Its simple interface and low cost, as there is no need for additional hardware, are the most prominent advantages of software firewalls. However, a significant disadvantage is that it consumes system resources by running continuously in the background, often causing system slowdowns.
Hardware Firewall: It filters the traffic and forwards it to the network if deemed appropriate. Its most significant advantage is that it does not affect the speed since it is not part of the computer’s operating system. However, the disadvantage is that it requires additional hardware, leading to increased costs. However, when both types of firewalls are examined, it can be said that hardware firewalls provide the best solution.

In addition to these, there are also firewall variations based on their architectural structures. First, second, and third-generation firewalls, UTM (Unified Threat Management), and next-generation firewalls are examples of these. The importance of firewalls for the security and sustainability of systems cannot be underestimated today. In this regard, we recommend reading our article ‘Network Solutions’ that we offer to businesses for their security needs.