Firewall – How it works?

Hey… Here today I came up with an article on Firewalls. I will speak about how it works and how are they useful for cyber security purpose. Well if you are a regular internet user then you might have heard of the word ‘firewall’ long time before. Well, I will explain it to you with a simple example, when an employee in his office tries to access a website such as social network they get a message “Firewall used” on their screen! This is what the function of a firewall. A firewall protects the entire corporate network so that hackers cannot enter into your private (corporate) network.

You might be wondering what a hacker must do knowing about firewalls! The answer is, a potential hacker can break into firewalls accessing the corporate network and ends up stealing Metadata or violating the network! Hackers bypass into firewalls using various techniques but today I will just give you a simple idea on firewalls.
Basically, a firewall is a potential barrier used to keep the hackers (and other violating scripts) away from the internal corporate network! A firewall is a piece of software which filters the packets of information received to your private network.
How it works?Suppose, you own a corporate network where you got few people working in you network. If you don’t protect your network with a firewall then the users on your network can access anything on internet and would leave their footprints as a result a potential hacker can exploit your network and steal your credentials. Mean to say, all those computers are directly accessible to anyone on the internet and a hacker who knows what the person is doing can probe those computers, try to make FTP connections to them, try to make telnet connections to them and so on. If one employee makes a mistake and leaves a link to the internal network, hacker can get to the computer and exploit the network. But if you use a firewall, your network is safe. A firewall will function with the help of a set of instructions which will prevent hackers access your network. If you setup instructions such as prevent all the users on this network using FTP or access a particular website or web server then you can control the people on your network connect to Web sites, sending files over the network etc.
Firewalls examine the source IP address of packets to determine if they are legitimate to the network. A firewall may be instructed to allow the access of person if it comes from a specific trusted host. A malicious hacker would then try to gain entry by “spoofing” the source IP address of packets sent to the firewall. If the firewall detects that, the packets originated from a trusted host, it may let them through.
A hacker can use a proxy to enter in to the corporate network as a legitimate. The cracker must need to know a good deal about the firewall’s rule base to exploit this kind of weakness.