Almost everyone knows the term “firewall”. But what exactly is behind it? Literally, firewall means something like “wall on fire”. You need a firewall to counteract the threat of viruses, worms, Trojans and hacker attacks. However, the firewall should not be confused with an anti-virus program. Unlike anti-virus software that identifies and destroys malicious viruses, a firewall monitors your network and determines whether traffic is allowed or blocked.
In order to decide which data packets are allowed through and which are blocked, there is a specific set of rules that are defined in advance. You can configure the settings of the rules according to your desired security standards. Especially in this day and age, a firewall is an absolute must for every company. The firewall prevents unauthorized connection attempts from the public network to the local area, thus protecting your data from attackers. Overall, the firewall is an important part of IT security.
Personal Firewall vs. external firewall
A firewall is always based on a software component whose installation location reveals whether it is a personal firewall or an external firewall.
For businesses, the external firewall solutions, also referred to as network or hardware firewalls, are mainly relevant. The concrete difference to the personal firewall lies in the fact that the software of an external firewall runs on a hardware. It is located between two network segments and can, therefore, restrict access between the two networks. For large enterprises, the external firewall is usually a standalone device. For home users or small businesses, however, often enough the external firewall, which is already integrated with many routers.
The personal firewall is also called a desktop or internal firewall. Here, the monitoring software is installed locally on the user’s terminal to be protected. Although it is easier and cheaper to install, but rather unsuitable for companies as a complete solution.
“For the highest level of security, we recommend a high-level firewall system. In doing so, several firewall concepts are combined intelligently. “
Which software levels are there?
A classic firewall works on different software levels, which can also be combined in different ways. Overall, a distinction is made between the packet filter, the circuit relay, and the application layer gateway.
In a packet filter, a decision is made on the basis of various criteria as to whether a data packet is allowed through, denied or rejected. The criteria include, for example, the source or destination address of the packet, the source or destination port of the packet, and the transport protocol.
The Circuit Relay technology, however, is much more complex and works at a higher protocol level with a subnet and two routers. For the users of an internal intranet, who want to move around the internet without restrictions, the Circuit Relay technology is ideal. In order to establish a connection to the intranet, the same access authorization must be proven. This prevents external users from drawing conclusions about internal network structures.
The concept of the Application Layer Gateway is the most elaborate, but also the safest solution of the three presented software levels. Here, the connection to the server is established via a proxy, so that there is only an indirect connection between client and server. The complete decoupling of the networks creates a high degree of computer security, but also a much higher computational effort. For the highest level of internet security, a high-level firewall system is recommended here. In doing so, several firewall concepts are combined intelligently.
Next Generation Firewalls
Due to the increasingly complex threat landscape and intelligent attacks by hackers, the security standard of a classic firewall is no longer sufficient for many companies. In particular, with the proliferating number of applications that are a particularly popular target for cyberattacks, careful traffic filtering is becoming increasingly important. Therefore, more and more Next Generation Firewalls (NGFW) are used, which have much more to offer than the control of traffic based on ports and protocols. Next Generation Firewalls provide comprehensive and layered protection against attacks and threats.
Classic firewalls examine the protocol and the port used and decide whether traffic is allowed or denied based on the rules set. Next generation firewalls, on the other hand, also examine the content of the data stream and can easily filter out infected files. Attacks that camouflage themselves as allowed applications can thus be detected much easier and faster. Furthermore, a feature of Next Generation Firewalls allows users to be associated with the rights. As a result, activities of existing users in the network are detected. Based on the defined policies, their access rights can be restricted.
In summary, firewalls are an absolute must for your organization’s network security and should be integrated into your IT security. However,even the best firewalls can never guarantee absolute security. They only ensure that as few attack points as possible arise. Firewalls can be used in many ways and on different levels. Next Generation Firewalls offer you an advanced defense against complex threats to your business.
Are you considering how you can make the IT security of your company particularly secure and would like individual advice on how to implement it?