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In today’s digital landscape, top-notch network security solutions are the need of the hour. Apart from concrete anti-malware programs and different cybersecurity solutions, having a proper network security plan with a good firewall is a must.

Traditional firewalls protect the internal network against the incoming traffic. They have been serving as the first line of defense in network security for almost the past three decades. Over this period, they evolved to become—traditional, next-generation, hardware, and software, to name a few. Like any other cybersecurity solutions, the firewalls have transformed since its initial years, thus making it challenging for network owners to decide upon the appropriate firewall to use as per their requirements. Choosing a wrong firewall can leave your network and data susceptible to various types of cyber threats.

All About Firewall

A firewall can be defined as either a hardware or a software program, designed to block all unwanted incoming traffic while allowing authorized communications to flow freely. As a security enhancement mechanism, the firewall filters out the flagged data packets as per the defined rules and standards. In simpler words, a firewall acts as a shield between the private network and the Internet to protect the former from unauthorized access.

A few basic facts about firewalls may be listed as follows:

  • Without a firewall, your internal network is under constant threat of unauthorized access, security breach, and data theft.
  • A firewall sometimes even prevents outgoing traffic from visiting certain websites or web pages to keep it safe from the unsafe environment.
  • The rules need to be defined by the administrator of the network to block unnecessary traffic from entering.
  • Routers vs. Firewalls—A router and a firewall are not the same. A router directs the traffic to the desired target without blocking any incoming traffic, except Access Control List (ACL). In fact, routing is one of the functions of a firewall with the primary objective of blocking unusual traffic.

Different Types of Firewalls

Organizations have several different types of firewalls to choose from, which are:

  1. Proxy Firewall

A proxy firewall filters out flagged messages at the application layer to protect the resources of a private network. Its add-on functionalities include content caching and provision of security for direct connections between internal and external networks. It is also known as an application firewall or gateway firewall.

  1. Stateful Inspection Firewall

A firewall blocking incoming traffic based on state, port, and protocol is known as stateful inspection firewall. Such firewalls monitor an active connection throughout its different states to check which network packet should be allowed to pass.

  1. Unified Threat Management (UTM) Firewall

A UTM firewall combines the features of a traditional firewall with various other security aspects. Usually, this UTM appliance offers the functionalities of gateway antivirus, intrusion detection, and prevention, which are loosely coupled together. Such firewalls are ideal for small- to medium-sized enterprises.

  1. Next-Generation Firewall (NGFW)

Next-Generation Firewalls are designed to block modern-day cyber threats, such as advanced malware and application-layer attacks. However, this firewall should also be capable of performing the standard stateful inspection.

  1. Threat-Focused NGFW

Apart from the functions of a traditional NGFW, threat-focused NGFW offers advanced threat detection and remediation. It also knows which assets are more prone to risk with a complete context awareness report. It can respond to attacks using intelligent security automation and is capable of handling various other security-related issues.

Why Do You Need Firewalls?

If you are doubtful and are still looking for more reasons to install a firewall, look at the following benefits of having an active firewall:

  • No More Unauthorized Remote Access

Consider a scenario where a cyber attacker can access your entire data and private accounts remotely; this can be prevented by disabling the “remote desktop access” feature of the firewall. Note that this feature is not capable of blocking manually allowed third-party applications to use your data. Also, if some malware program is pre-installed in your system, which usually comes along with other security issues—like Trojans, keyloggers, and backdoors, then a firewall is incapable of protecting your network and data.

Note: As firewalls are designed to block malicious apps from gaining access to the private network, there is a probability that a few trustworthy software and applications can also be blocked.

  • Blocking Unwanted Messages

Anti-spam feature of firewall helps in controlling, detecting, and preventing unwanted messages, which can contain spam, viruses, or any other threats. This responsibility makes it crucial to keep your firewall active and appropriately configured. If not done correctly, you will be an easy target for cyber attackers.

  • Safe Online Gaming Experience

Online gaming brings potential cybersecurity risks while being one of the most significant developments in the gaming world. McAfee has recently reported in its survey “Game Over” that 75 percent of PC gamers are concerned about the security aspect of future gaming. [1] This problem has a great solution—firewall installation.

Mostly, firewalls are designed to configure themselves according to the requirements of the game. It will update the firewall with a suitable title, software type, and any other required attribute. The “Gaming Mode” of most of the games helps the gamers to automate the security-related configurations. They will also get the option of changing the firewall application settings to manual.

  • Filtering Out Immoral Content

With all the above-listed pros, firewalls can protect directories and folders from ransomware and can even block specified online locations. This setting usually comes under parental control, but this feature is similar to the roles and responsibilities of a firewall too.

Firewall Rules

Firewalls follow the fundamental constraint of matching the incoming traffic with the defined rules to allow it to get through. The following instances give you a closer look at how firewall rules are applied:

Example 1: Accept established incoming traffic to the public network interface on port 80 and 443, which stands for HTTP and HTTPS web-based traffic.

Hypertext Transfer Protocol (HTTP) is an “application layer protocol” responsible for presenting information rather than focusing on how data gets transferred from one point to the other. HTTP is suitable for those websites that do not hold sensitive information. On the contrary, HTTPS (or “secure http”) allows authorized access and secures transactions. Note that HTTP and HTTPS don’t pay attention to the transfer of data.

Example 2: Reject incoming traffic from public networks on port 22 (SSH).

The SSH protocol (or “Secure Shell”) allows secure remote login. It offers several features like authentication, communication security, and integrity with robust encryption. SSH is a substitute protocol for other login protocols, such as telnet and rlogin, which not protected in nature. It can also be used in place of FTP, which is again an insecure file transfer protocol.

That’s how the firewall rules are applied to avoid unwanted network traffic.

Cybercriminals targeting small- to large-scale businesses—this has become a common cybersecurity issue. To avoid this, you should prepare yourself with a line of defense containing a properly configured firewall, the one that can fulfill the security requirements of your organization. Choose between hardware and software firewalls or install both to add an extra layer of security. A proactive firewall can protect your organization from various malware attacks and unauthorized intrusions.

Become a Certified Network Defender

EC-Council’s Certified Network Defender (CND) teaches you secure firewall configuration among other network security protocols and controls to achieve defense-in-depth security. The program will help you protect, defend, and respond to network security threats. Learn more about the certification by visiting https://www.eccouncil.org/programs/certified-network-defender-cnd/