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Introduction:
Firewall these days are an important component of network security and we cannot ignore them. We are living in a world where the Internet is a necessity for a majority of the population. Whether to update profile pictures on social media or posting status we need internet connectivity.
Furthermore, this covid-19 pandemic has increased the overall importance of the internet. It is due to the internet people started doing work from home jobs. This made people earn money for their living and at the same time, they are safe from the infection.
When we are talking about this covid-19 pandemic, children were also able to continue their studies with the help of the internet. And there are several many reasons that reflect the importance of the internet in our lives. So now, coming back to the Topic What is a Firewall? Why do we need it? and several many questions that may come to your mind will be cleared in this article so keep reading.
In simple terms, A firewall is a software or hardware or a combination of both that monitors and filter incoming and outgoing traffic based on certain security rules. This basically works as a barrier between the private network and the public internet. In addition to that, it blocks malicious traffic that tries to get inside the private network and allows only good traffic.
For the larger companies, this network security component is very important to protect their sensitive data from hackers. There can be several harmful consequences of not using a firewall on a constantly evolving internet. Also, It will be a good practice to use both hardware and a software-based firewall.
Why Firewall is important?
The main task of a firewall is to prevent network-based attacks and also to prevent malware. Moreover, it monitors every action between the internet and the internal private network. It can only allow data packets from incoming or outgoing until and unless the source is user trusted.
Also, the cloud-based firewall exists in this world. And they are commonly known as FaaS (Firewall as a Service). In addition to that, let us see some risks of not using a firewall:
Open Access:
When not having this network security technology in our private network, we are giving everybody access to our network. And the absence of a firewall can lead to undetected malicious connections or attacks. That will be a very serious situation if anybody is running a big organization.
Data Will be compromised:
If it is absent in your private network then anybody can get access to any computer within the network. And guess what, this will result in compromised or damaged data. If one is running a big organization then the absence of this security technology can leak internal data of the company on the public internet.
Network Crashes:
If this component is absent in a network then anybody can get access easily and can even crash the network. This will cause unnecessary problems in our network and will waste our valuable time.
How does a firewall work?
The working of a firewall is very simple, It has some predefined rules in it. And if any traffic source is suspicious and not allowed in the rules. Then this technology simply blocks it and prevents some unwanted traffic on the network. On a network, this thing generally stops traffic on a computer’s entry point generally termed as a port.
Types of Firewall:
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As I have mentioned earlier in the blog post this network security component can be software, or hardware or can be a combination of both. There are several types of firewalls available in the market today but all of them has a common objective i.e. to protect the private network from malicious attacks.
Furthermore, A hardware-based firewall is known as Appliance Firewall. And on the other hand, software-based firewalls is popularly termed as Host Firewall. When talking about its types there are 9 different types of Firewall in the market and they are:
- Packet-filtering Firewalls.
- Circuit-level Gateways.
- Application-level Gateways (Proxy Firewalls).
- Stateful Multi-layer Inspection (SMLI) Firewalls.
- Next-generation Firewalls (NGFW).
- Threat-focused NGFW.
- Network Address Translation (NAT) Firewalls.
- Cloud Firewalls.
- Unified Threat Management (UTM) Firewalls.
So let us discuss each one of them one by one.
Packet-filtering Firewalls:
This type is the most basic type of firewall. In addition to that, this behaves as a management program that monitors the network traffic as well as filters data packets completely based on the rules. This type of firewall has the capability to block IP protocols, port numbers as well as IP addresses.
This kind of Firewall technology utilizes a very low amount of resources and the configuration time required is also very less. But it has some limitations like it cannot prevent web-based attacks so this cannot be fully safe.
Circuit-level Gateways:
This is the another simplest type of Firewall in the market. It is also easy to configure and use less amount of resources. Circuit-level Gateways operates on the session layer of the OSI Model. So this type of firewall ensures that sessions remain protected. This is also not a safe kind of firewall like the packet-filtering firewall. So now let’s see another one.
Application-level Gateways:
Application-level Gateways are also known as Proxy firewalls. This acts like a middle person between internal networks and outside webservers. It filters messages at the application layer, so this way it helps in the protection of the network.
Stateful Multi-layer Inspection (SMLI) Firewalls:
This type of firewall is way much better than Packet-filtering and circuit-level firewalls. I am saying this because it performs packet inspection and TCP ( stands for Transmission Control Protocols) handshake verification at the same time. This makes it better than those two firewalls.
Next-generation Firewalls(NGFW):
Those firewalls which are released newest are usually termed as Next-generation Firewalls. This type of firewall combines the features of other firewalls. Moreover, the features of this kind of Firewall includes DPI (short for Deep Packet Inspection), TCP handshaking, Surface-level Packet inspection, and so on.
Threat Focused NGFW:
These kinds of firewalls include all the features of traditional NGFW. Moreover, It protects the network from advanced threats and also neutralizes them. It reacts against the attacks quickly and efficiently.
NAT Firewalls:
NAT stands for Network Address Translation, and this kind of firewall is specially created for accessing the internet and to block all malicious connections. And this kind of firewall hides the IP address of the devices present in our network, thus making our devices safe from attackers.
Cloud Firewalls:
Those Firewalls that are created using the cloud platforms are usually termed as Cloud Firewalls. It is also known as Firewall-as-a-service or in short FaaS. The biggest advantage of this kind is scalability. From that, I mean to say that one can easily scale this kind of firewall as per the need of the company.
UTM(Unified Threat Management) Firewalls:
This kind of firewall contains many features like intrusion prevention support, stateful inspection Firewall with Anti-Virus and so on. This kind of technology is easy to use and simple.
So this was all about the firewalls, don’t forget to comment your thoughts in the comment box below. And thanks For reading the post and I will see you in the next one.
