Imagine a house without a boundary wall. This will may allow anyone to rob the house easily. Therefore, the house will be at very high risk. Hence, a boundary wall protects our property.
Similarly, imagine our computers and networks without protection. This will increase the probability of hackers attacking our system. To overcome this problem, same like how a boundary wall protects our property, a virtual wall protects our computer and network from cyber-attacks. These walls are called Firewalls.
Firewalls are security devices that filter incoming and outgoing traffic within a private network. It acts as a gatekeeper at the entry point of our computer and allows incoming non-threatening traffic. It filters the network traffic and analyses which traffic should be allowed based on the defined set of security rules.
Our computer communicates with the internet in the form of packets which holds the details like source address, destination address, and information.
When we connect our computer to the internet there is a high chance for Cyber Attacks. Here comes the firewall to protect our system and acts as a barrier between the computer and the internet.
A firewall rejects malicious data packets. Thus, protects the computer from hackers and allows data packets from trusted websites.
Types of Firewalls
Firewalls can be hardware and software. Software firewalls are the computer programs that are installed on each computer. These firewalls are also called Host Firewalls. Linksys routers are the best example of hardware firewalls.
There are other types of firewalls designed based on their :
- Traffic filtering methods
Packet Filtering Firewall
A firewall that compares a network packet with a set of rules such as IP addresses, IP protocols, and port numbers is called a packet filtering firewall. The incoming packet which does not satisfy the predefined rules is not allowed.
Stateful Inspection Firewall
These type of firewalls not only examines each packet but also checks whether the network packet is part of an established connection or not. These firewalls are also called Dynamic Packet Filtering Firewalls.
Proxy firewalls pretend to be you and interact with the internet and provide protection to our computers. Only protected and safe traffic is sent to the computer and these types of firewalls are also called Application-level gateway firewalls.
Circuit-level Gateways Firewall
Circuit-level gateways are typically used to protect internal networks from external threats by implementing security policies such as authentication and encryption.
Network-Address Translation Firewall
These types of firewalls usually hide the IP addresses of our devices, making them safe from attackers.
Whenever a firewall is designed using a cloud solution, it is known as a cloud firewall.
Unified Threat Management Firewall
UTM firewalls are a special type of device that includes features of a stateful inspection firewall with anti-virus and intrusion prevention support.
These Firewalls are used in educational institutions, and offices to prevent data from Cyber Attacks.