A firewall can be either software (computer program or application) or hardware (a special computer that is running a firewall program) which serves to filter the traffic of computer networks and the Internet. Firewall protection is needed, especially for computers connected to the internet connection. Firewall improves the security of computer networks by providing detailed information on network traffic patterns. Firewall is indispensable as a security gateway between the internal networks that is relatively safe with external vulnerable networks (the Internet).
How it works
• All network communications pass through the firewall
• Only the data traffic from a trusted network that is allowed through the firewall
• Firewall has the ability to protect computers from malicious attacks originated from the Internet
The computer has thousands of ports that can be accessed for a variety of purposes. Firewall computer has a duty to close the ports unless some ports that need to be kept open. Firewall in computers also act as a first line of defense in preventing all types of hacking. As we have seen, hackers generally work by trying to break into a computer network through an open port.
In addition, there are also a variety of other uses of the firewall as follows:
• Firewall is useful to maintain confidential and valuable information to keep it out without being noticed by the user. For example, traffic of FTP (File Transfer Protocol) of an organization is generally controlled by the firewall. This is done to prevent users on the network to send confidential file either intentionally or accidentally to any other party.
• Filter of firewall is also used to prevent certain traffic flowing into the subnet network. It is useful to prevent users from sharing music and playing games on the network. This type of application is useful especially in the corporate sector.
• Another important utility of a firewall is to modify the data packets coming through the firewall. This process is called Network Address Translation (NAT). There is a type of NAT called a basic NAT where the private IP (Internet Protocol) address of a computer network is hidden behind one IP address.