What does a computer firewall mean, what does a firewall on a computer mean? What s the use?

Definition of a firewall:

A firewall is a protective barrier constructed on the interface between the internal network and the external network, and between the private network and the public network, which is composed of software and hardware devices. It is a combination of computer hardware and software, so that a security gateway (security gateway) is established between the Internet and the intranet, so as to protect the intranet from the intrusion of illegal users, the firewall is mainly composed of four parts: service access policy, verification tool, packet filtering and application gateway, the firewall is a software or hardware located between the computer and the network it is connected to ( Among them, hardware firewalls are rarely used, and only in places such as the Ministry of Defense are used, because it is expensive). All network traffic to and from the computer passes through this firewall.

Features of the firewall:

The firewall scans the network traffic that flows through it, which filters out some attacks before they are executed on the target computer. Firewalls can also shut down ports that are not in use. It also prohibits outgoing traffic on specific ports and blocks Trojan horses.

Finally, it can prohibit access from special sites, preventing all communication from unknown intruders.

Firewall: It is to compare the interference information from the outside world, uneasy software and unwanted information that is harmful to the computer to fire, and the firewall can be installed to resist the interference of those information.

A computer firewall is! Prevent viruses in your computer @ and dangerous software reminders!

When the program on your computer needs to be connected to the Internet, it will prompt you whether to allow it or not, and if you click it wrong, it will be super troublesome! It's useless, forbidden! Replace it with 360.

Security system to prevent hackers and other intrusions.

It's to prevent hacking and so on.

Firewall, also known as Protective Wall, was invented and introduced to the Internet in 1993 by Gil Shwed, the founder of Check Point (US5606668(A)1993-12-15). It is a network security system that sits between the internal network and the external network. An information security protection system that allows or restricts the passage of transmitted data in accordance with specific rules.

Originally, it refers to the wall that isolates the fire from causing greater damage. An application on a network is a device that isolates the internal network from the external network to protect the security of the internal network.

Tools to prevent Trojans and other malware from invading your computer are your computer's shield, and antivirus software is your spear.