The most important and precious asset we have today is our Data, and protecting it should be our first task. However, there are many challenges that we face while protecting it. One of the best solutions for this problem is a firewall. It will help us to protect our data and our systems. In this post, we will be learning about firewalls, their types, and their working principle.
Table of Contents
What is a Firewall?
A firewall is a security device that monitors and controls incoming and outgoing network traffic based on predefined rules. As the name suggests, it works as a wall that protects our system from the outside untrusted network, the Internet.
The user sets some security rules and on that basis, it accepts, rejects, or drops that specific network. Firewalls can be hardware or software-based and are commonly used in networks to enhance security and enforce access policies. It safeguards our system from unauthorized access and cyber threats. Firewall security is basically used by large organizations for whom data security is a major concern.
How does a firewall work?
As discussed above, firewalls are the devices that allow trusted networks and reject untrusted and unwanted networks into our system. The device allows us to set some safety rules initially and on that basis the incoming network traffic is judged and appropriate action is taken upon them.
For example, just imagine the watchman appointed at the college gate. The work of the watchman is to check the student entering the college and to either allow him to enter the college or not, based on some basic guidelines set by the college. The student will carry their identification card (IP address, source address in the case of network) and if it is unauthorized or untrusted then the student will not be allowed to enter the college.
The firewall works similarly to the watchman and welcomes only incoming traffic that has been configured to accept, authorized, and trusted.
As shown in the above figure, the network has its own IP address, protocol, destination address, and port number. On this basis, the network is either given the access or not.
Types of Firewall
Firewalls are categorized into two types:
- Host-based Firewalls: It is a software application that comes along with the operating system. Each host’s firewall protects it against attacks and unauthorized access. Each network node has a host-based firewall that controls all incoming and outgoing information. Host-based firewalls are needed because network firewalls cannot provide protection inside a trusted network.
- Network-based Firewalls: Network firewalls are the hardware-based system present on the network level. In other words, a Firewall filters traffic going from the Internet to a secured LAN and vice versa. A Network firewall might have two or more network interface cards (NICs). A network-based firewall works as a different dedicated system with software installed.
Advantages of firewall
Firewalls play a significant role in security management in businesses. The following are some of the most significant benefits.
- It improves security and privacy when using susceptible services. It keeps unauthorized users from connecting to a private network that is linked to the internet.
- Firewalls respond faster and can manage higher traffic loads.
- A firewall makes it possible to manage and update security protocols from a single authorized device.
- It protects your network from phishing assaults.
- Firewalls can be configured to restrict traffic associated with known malware or other security problems, assisting in the defense against such attacks.
Disadvantages of Firewall
- For a bigger network, setting up a firewall can be time-consuming and difficult. Because firewalls are often rule-based, they may be unable to respond to new security threats.
- It can have a substantial impact on network performance, especially if they are configured to analyze or control a large amount of traffic.
- Purchasing many devices or add-on features for a firewall system can be costly, particularly for enterprises.
- Some firewalls may not support advanced VPN capabilities such as split tunneling, limiting a remote worker’s experience.
application of firewall
- Firewalls are frequently used to protect corporate and household networks from external dangers such as hackers, viruses, and unauthorized access. They monitor incoming and outgoing network traffic, permitting or prohibiting data packets depending on established security rules and policies.
- Web Application Firewalls (WAFs) are specially designed to defend web applications from various online threats such as SQL injection, cross-site scripting (XSS), and other web-based attacks. They filter and analyze HTTP requests in order to identify and block harmful activity, hence assisting in the security of websites and online services.
- Firewalls are used by intrusion detection systems (IDS) and intrusion prevention systems (IPS) to detect and block suspicious or malicious network activity. These systems analyze traffic patterns and behavior in order to detect potential security vulnerabilities and provide real-time alerts and automatic solutions to mitigate risks.
- Email Firewalls are used to protect email servers against spam, phishing attempts, and malware transmitted by email attachments or links. To prevent data breaches, they monitor incoming and outgoing email traffic, scanning for known risks and enforcing email security regulations.
- Cloud-based firewalls are used to safeguard applications and resources hosted in cloud platforms such as Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform. These firewalls contribute to the security of cloud environments by restricting network access, filtering traffic, and enforcing security policies in order to prevent unauthorized access and data breaches.