firewall

Firewall is a software program or piece of hardware that helps screen out hackers, viruses, and worms that try to reach your computer over the Internet. When connected to the internet, even a standalone PC or a network of interconnected computers make easy targets for malicious software & unscrupulous hackers. A firewall can offer the security that protects your data from being compromised or your computers being taken hostage.

A firewall is a network security device that grants or rejects network access to traffic flows between an untrusted zone (e.g., the Internet) and a trusted zone (e.g., a private or corporate network). The firewall acts as the demarcation point or “traffic cop” in the network, as all communication should flow through it and it is where traffic is granted or rejected access. Firewalls enforce access controls through a positive control model, which states that only traffic defined in the firewall policy is allowed onto the network; all other traffic is denied (known as “default deny”).

Firewalls are setup at every connection to the Internet, therefore subjecting all data flow to careful monitoring. Firewalls can also be tuned to follow "rules". These Rules are simply security rules that can be set up by yourself or by the network administrators to allow traffic to their web servers, FTP servers, Telnet servers, thereby giving the computer owners/administrators immense control over the traffic that flows in & out of their systems or networks.

Rules will decide who can connect to the internet, what kind of connections can be made, which or what kind of files can be transmitted in out. Basically all traffic in & out can be watched and controlled thus giving the firewall installer a high level of security & protection.

It is recommended using firewall in such cases:

1. If you use a computer at home, the most effective and important first step you can take to help protect your computer is to turn on a firewall.
2. Windows 8, Windows 7, Windows Vista, and Windows XP SP2 or higher have a firewall built-in and turned on by default. (Note: Support for Windows XP ended in April 2014.)
3. If you have more than one computer connected in the home, or if you have a small-office network, it is important to protect every computer. You should have a hardware firewall (such as a router) to protect your network, but you should also use a software firewall on each computer to help prevent the spread of a virus in your network if one of the computers becomes infected.
4. If your computer is part of a business, school, or other organizational network, you should follow the policy established by the network administrator.