What is a firewall?
Most of you people who have a keen interest in software and security really want to know about firewalls too so a firewall is basically a network security device that monitors incoming as well as outgoing network traffic and decides whether to allow or block specific traffic based on a defined set of security rules.
For over 25 years Firewalls have been the first line of defense in network security. A firewall establishes a barrier between secured and controlled internal networks that can be trusted and untrusted outside networks, like the Internet. One thing you should know is a firewall can be hardware, software, or both
Why install a firewall?
Numerous Linux distributions transport with a firewall as of now introduced, and customarily that was iptables. It is amazingly compelling and customizable, but it can be complex to design. Fortunately, designers have created a few frontends to assist clients to control their firewall without composing long iptables rules. Fedora, Red Hat, and similar distributions the Linux software firewalls installed by default are firewalled which is configured and controlled with the firewall-cmd command. On most other distributions firewalled is available to install from your software repository. Iptables is considered as best Linux firewall distribution,
How does a firewall work?
Firewalls will delicately analyze incoming traffic based on pre-established rules and filter the traffic coming from unsecured or suspicious sources to prevent attacks. Firewalls act as guard traffic at a computer’s entry point which is called ports which is where information is exchanged with external devices. Just for example, “Source address 220.127.116.11 is allowed to reach destination 18.104.22.168 over port 22.”
For your easy understanding just think of IP addresses as houses and port numbers as rooms within the house. Only trusted people means source addresses are allowed to enter the house means destination address. It’s then further filtered so that people within the house are only allowed to access certain rooms’ means destination ports depending on if they’re the owner, a child, or a guest. The owner is allowed to go in any room (any port), while children and guests are allowed into a certain set of rooms (specific ports).
Types of firewalls:-
a). Proxy firewall
b). Stateful inspection firewall
c). Unified threat management (UTM) firewall
d). Next-generation firewall (NGFW)
e). Threat-focused NGFW
f). Virtual firewall
What is a Linux Firewall?
A Linux firewall is a device that inspects Network traffic whether ingoing or outgoing connections and makes a decision to pass or filter out that traffic. Iptables is a CLI tool for managing firewall rules on a Linux machine.
Network Security has evolved with different types of Linux firewalls in a different era. Like traditional packet filtering firewalls deal with Routing and filtering packets where else NGFWs will work with additional functions as with OSI layers.
In order to be a successful Linux system administrator, you must be ensuring the security of the Linux systems or network infrastructure plays an important role. For establishing tight security management you have to use certain rules in the Linux firewall. Different Linux firewalls rules control and manage incoming and outgoing network traffic and only allow legitimate connections between internal and external networks.
Although Linux distributions usually come with a free firewall application bundled with it. Most often this will not be active by default so it will need to be activated. In addition to this will likely be the standard Iptables supplied even though less experienced users may struggle with it first. The UFW Uncomplicated Firewall is also bundled with some distributions and aims to make the process simpler.
However, there are distributions and applications out there that can be easy for the less experienced user as well as the more advanced one making it easier to set up and configure a firewall that works for your needs. But not all are free especially when it comes to business applications.
For example, some like ClearOS build a firewall directly into the operating system as part of its security focus, but most other options would be applications that aim to block scoundrel IPs, monitor ports, and otherwise prevent bad packets from interfering with your machine.
For the people who use it in their personal computers, for most home users few actual settings need to be customized so simple apps can be popular, but for those looking to manage their machine as a server with additional controls and advanced command, options will tend to be the more welcome.
Top 10 Linux software:
Being a new user of Linux at first you’ll feel some difficulty. Sometimes you may feel your Linux system is scary and very confusing if you have recently come from Windows or Mac OS. But interestingly Linux software is not like that. Here you will be able to enjoy the freedom of using a lot of amazing Best Linux software which comes free of cost mostly. In this article, we will be going to focus on a list of Best Linux software which will help Linux users to get the latest and best Linux apps from different categories.
For having the best software for Linux it is all subjective and depends on users’ needs. Interestingly in the Linux software world, there are lots of alternatives to every software like many distros to choose from. So while making up the list we tried to include the one which generally comes with the essential tools and features for accomplishing the purpose.
Here is the list of best Linux firewalls:-
5. pfSense. …
6. IPFire. …
7. SmoothWall & SmoothWall Express
9. ConfigServer Security Firewall
Other than these top Firewalls there are many other firewalls like Sphirewall, Checkpoint, ClearOS, Monowall available on the web to secure your Linux box. Let us know which one is your favorite firewall and leave your valuable suggestions and queries below in the comment box.