Information security is becoming more important as the incidence of cybercrimes rises. There are, however, considerable obstacles to doing the same. The use of a firewall is only one method of protecting your network and other devices from potential threats. You will find out all you need to know about firewalls and how they secure your network in this comprehensive “what is a firewall” guide.
Let’s get started by defining firewall.
What is Firewall?
Firewalls guard against malicious code and firmware that may otherwise compromise a network. The firewall checks all incoming and outgoing data for violations of its rules and prevents any that it finds.
A fence around your home serves the same purpose as a firewall around your computer network: it prevents unauthorized users from accessing sensitive information. Firewalls are security solutions for networks that block out intruders. A firewall is a hardware or software component that filters data entering and leaving a private network based on predetermined rules designed to identify and stop cyberattacks.
Firewalls may be found in both business and home networks. When it comes to keeping your network safe, they are an absolute must-have. Many OSes already have a firewall installed, even if it’s only a simple one. However, a separate firewall program offers more security.
Since we now know what a firewall is, we can go on to learning about their development and use in the past.
Why are Firewall Important?
Modern security strategies are included into the design of firewalls, and these strategies find utility in a variety of contexts. Since the client-server paradigm is at the heart of today’s computer infrastructure, it was imperative that networks be constructed in those early days of the internet with novel security measures. This is where firewalls have begun constructing the safety for networks of various complexity. Firewalls are often used to protect systems from outside danger by analyzing incoming data.
Key Uses of Firewalls
1. Firewalls are useful in both business and home networks.
2. Firewalls, which are often placed at the network perimeter of contemporary businesses in order to protect against both external and internal threats, may combine a security information and event management strategy (SIEM) into cybersecurity equipment.
3. Firewalls can keep track of activity, conduct audits, and make their rules more effective by adapting to new threats as they emerge.
4. Firewalls are useful for private networks with fixed IP addresses, such as those connected through DSL or cable modem. Filtering network traffic and alerting users of intrusions are two of the many useful features offered by firewalls.
5. Firewalls update their rule sets to address vendor concerns as new threats or updates become available.
In what way does a firewall protect a network?
In a private network, traffic is filtered using firewalls, as was discussed before. It determines, according to predetermined criteria, whether forms of traffic should be permitted or prohibited. The firewall acts as a guard at the door of your computer, allowing only authorized visitors (known IP addresses) inside.
Only the incoming traffic that has been approved by the firewall’s settings is let through. It analyzes data packets based on a set of security criteria and decides whether to allow or block them based on whether or not they conform to those rules.
Several characteristics of the packet data, such as its origin, destination, content, etc., serve as the basis for these rules. Cyberattacks may be averted if they are able to restrict traffic from potentially malicious sources.
Here is an illustration of how a firewall will allow only trusted data to enter the user’s internal network.
Fig: Firewall allowing Good Traffic
However, in the case below, the firewall prevents the cyberattack by preventing the malicious traffic from accessing the private network.
Fig: Firewall blocking Bad Traffic
In this manner, a firewall is able to do rapid evaluations in order to identify malicious software and other forms of intrusion.
To inspect data packets at various network layers, firewalls come in a variety of forms. Next, you’ll learn about the various firewalls available and how they work.
Types of Firewalls
It is possible to use either software or hardware to create a firewall. Computers with software firewalls installed may control what programs and ports are allowed to communicate with one another on a network. Hardware firewalls, meanwhile, are the physical barriers installed between your network’s gateway and your internal systems. The term “cloud firewall” is also used to describe a firewall that is provided via a cloud-based service.
Different kinds of firewalls exist because of the differences in how they are built, what kind of traffic they can filter, and what other features they provide. There are several types of firewalls, including:
What Is Packet Filtering?
Access to and egress from a network may be regulated by using a firewall that employs packet filtering. The packet’s source and destination addresses, as well as the application protocols being used to transport the data, are all taken into consideration before deciding whether or not to allow the packet to pass through.
Proxy Service Firewall
This firewall safeguards the network by inspecting and modifying messages at the application layer. An application-specific proxy firewall acts as the interface between two networks.
State Inspection
The firewall’s ability to allow or deny network traffic is determined by the user’s specified state, port, and protocol. Filtering decisions are made in this case according to the rules and context set by the administrator.
Next-Generation Firewall
Next-generation firewalls, as defined by Gartner, Inc., go beyond traditional port/protocol inspection and blocking to include application-level inspection, intrusion prevention, and external data.
Firewall for Unified Threat Management
In a nutshell, a unified threat management (UTM) device combines the features of a stateful inspection firewall, intrusion prevention, and antivirus software. Additional services and, often, cloud-based administration, may be a part of it. For this reason, UTMs prioritize making their interfaces intuitive and easy to use.
Threat-focused NGFW
These firewalls can identify and neutralize even the most sophisticated threats. They may be able to spot sneaky or malicious activity with the use of network and endpoint event correlation.
Use of Firewalls and Its Benefits
Now that you know the different kinds of firewalls, let’s talk about the benefits of installing and utilizing them.
1. Firewalls are crucial to the effective administration of security in businesses. Some of the major benefits of firewalls are listed below.
2. It protects users’ privacy and security while using potentially unsafe services. A private network that is also linked to the internet is protected against intrusion in this way.
3. Firewalls have greater throughput and reaction time than non-firewall alternatives.
4. A firewall makes it simple to manage and update all of your network’s security settings from a central location.
5. It prevents phishing assaults on your network.
How to Make Use of Firewall Security?
Protect your network and its components by properly configuring and maintaining your firewall. If you want a more secure firewall, consider these suggestions:
1. Always install new firewall software as soon as it becomes available: Your firewall’s defenses will be up-to-date against newly found vulnerabilities thanks to firmware fixes.
2. In addition to firewalls, antivirus software is essential for keeping your computer free of viruses and other malware.
3. Accessible ports and hosts should be restricted, with only pre-approved incoming and outgoing IP addresses allowed.
The best way to prevent network outages is to maintain an active network with several redundant connections. Maintaining backups of data on network hosts and other mission-critical systems is important for protecting against data loss and preserving business continuity in the event of a catastrophe.
Several Limitations Inherent in the Use of a Firewall
1. Because firewalls are unable to prevent users from accessing data or information from malicious websites, users remain susceptible to assaults or threats that originate from inside their own organizations.
2. If the security rules are not specified properly, it is unable to guard against the transmission of data or software that have been contaminated with a virus, as well as non-technical security hazards (social engineering)
3. It does not prevent the abuse of passwords or prevent attackers with modems from dialling in to or out of the internal network.
4. It does not safeguard systems that are already infected since firewalls do not protect them.