What is Firewall in computer networks and softwares ? | TechnoDaily

What is Firewall?

 Today we use a firewall in our computer networks to isolate our network and hosts from the danger posed by our neighbors.

To be precise, A Firewall may be a network security device that monitors and filters incoming and outgoing network traffic supported by an organization's established security policies and rules. At its most elementary, a firewall is actually the barrier or wall that sits between a personal internal network and the public Internet networks. 

Firewalls protect us from the unauthorized use of our resources by external entities. To be simple, a fireplace wall is employed to guard one unit during a multi-unit building from a fire that happens in an adjacent unit. The hope is that the firewall will isolate each unit from a disaster in one among its neighbors. Why does one want to be protected?

      So as to satisfy the three principles of confidentiality, integrity, and availability—you got to address the risks you’ve identified. this might mean you would like to be shielded from the wide-open Internet. It’s a scary place out there. you'll also get to isolate select hosts from the remainder of your network. In its simplest form, a firewall examines your communications requests (network traffic) and decides, supported rules you've got defined, what's and isn't allowed.

       Really, a really straightforward function—on paper, anyhow. Complications are introduced by the various ways to realize this goal. and every method has its own strengths and weaknesses. Traditionally, corporations have firewalls only at the perimeter of the network—where the company network meets the web. 

  

                     However, the normal network is changing. Users connect from home with high-speed Internet connections like cable modems, and sensitive data is being stored on local hard drives. These changes often make it necessary to think about protecting the local host with its own firewall software. And this is often where personal firewall software plays a task.