What does firewall mean? What is the use?

I believe many people have heard of firewalls, but for newcomers, they may not know what firewalls mean and what their uses are. This article will take you to understand firewalls.

What is a firewall?

A firewall is a network security device that can be hardware, software, or both; it acts like a physical barrier to limit the damage that a fire can cause, Virtual barriers can be set up to limit damage from external or internal cyberattacks.

Firewalls have always been considered the first line of defense to protect sensitive information. They create a barrier between secure and controlled internal networks, providing low-level network protection, as well as important logging and auditing capabilities. It monitors incoming and outgoing network traffic and decides whether to allow or block specific traffic based on a defined set of security rules.

Types of firewalls

Types of firewalls include: proxy firewall, stateful inspection firewall, unified threat Management (UTM) firewall and next-generation firewall (NGFW), let’s take a look at it below:

Proxy firewall:

Proxy firewall is a Network security system, which is an early type of firewall device. It protects network resources by filtering messages at the application layer and can also be called an application firewall or gateway firewall.

Proxy firewalls are considered the most secure type of firewall because they block direct network contact with other systems. Its ability to inspect entire network packets, not just network addresses and port numbers, also means that the proxy firewall will have extensive logging capabilities, which is a valuable resource for security administrators dealing with security incidents.

Stateful Inspection Firewall:

Now considered a "traditional" firewall, a stateful inspection firewall allows or blocks based on state, port, and protocol flow. It monitors all activity from the time a connection is opened until it is closed. Filtering decisions are based on administrator-defined rules and context that use information from previous connections and packets belonging to the same connection.

Unified Threat Management (UTM) Firewall:

A Unified Threat Management (UTM) system is a network hardware device, virtual appliance or cloud Services that protect enterprises from security threats in a simplified way by combining and integrating multiple security services and capabilities.

UTM devices are often packaged as network security appliances that can combine the capabilities of a stateful inspection firewall with intrusion prevention and antivirus; helping to protect the network from combined security threats, including malicious actors targeting different parts of the network simultaneously Software and attacks.

Next Generation Firewall (NGFW):

Next Generation Firewall (NGFW) is part of the third generation firewall technology and can be implemented in hardware or implemented in software and capable of detecting and blocking sophisticated attacks by enforcing security policies at the application, port and protocol levels.

Functions that NGFW can implement:

1. User identification and protection

2. Application Usage, visibility and control

3. Secure encrypted traffic

4. Detect and prevent advanced threats

5. Deployment flexibility

6. Sharing Threat Intelligence

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