What is a firewall and what are its advantages?

The so-called firewall refers to the protective barrier composed of software and hardware equipment, which is built on the interface between internal network and external network, private network and public network. This is an image expression of gaining a sense of security. It is the combination of computer hardware and software, and it is the security gateway between Internet and Intranet. So as to protect the intranet from illegal users. Firewall is mainly composed of four parts: service access rules, verification tools, packet filtering and application gateway. A firewall is software or hardware located between a computer and the network to which it is connected. All network traffic and data packets entering and leaving this computer must pass through the firewall.

Main advantages:

(1) Firewall can strengthen the security policy.

(2) Firewalls can effectively record the activities on the Internet.

(3) Firewall limits the exposure of user points. Firewalls can be used to separate different network segments. In this way, problems affecting one network segment can be prevented from spreading to the whole network.

(4) Firewall is the checkpoint of security policy. All incoming and outgoing information must pass through the firewall, which becomes a checkpoint of security issues, so that suspicious access is denied.