The so-called "firewall" refers to a method of separating the internal network and the public access network (such as the Internet). It is actually an applied security technology and isolation technology based on modern communication network technology and information security technology. It is more and more used in the interconnection environment of private network and public network, especially to access the Internet network.
The firewall mainly uses hardware and software to create a protective barrier between the environment of the internal and external networks, so as to block computer insecure network factors. Only when the firewall agrees, users can enter the computer. If they do not agree, they will be blocked. The alarm function of the firewall technology is very powerful. When an external user wants to enter the computer, the firewall will quickly send out the corresponding It also reminds users of their behavior, and makes self-judgment to determine whether to allow external users to enter the interior. As long as they are users in the network environment, this firewall can perform effective queries and direct the information to The user displays it, and then the user needs to implement corresponding settings on the firewall according to his own needs to block user behavior that is not allowed. Through the firewall, the flow of information and data can be effectively viewed, and the upload and download speed of data information can also be grasped, which is convenient for users to have a good control judgment on the use of the computer. The internal situation of the computer can also pass through this firewall For viewing, it also has the function of starting and closing programs, and the log function in the computer system is actually a summary and sorting of the real-time security situation and daily traffic situation of the computer's internal system by the firewall. [2]
A firewall is an access control measure implemented when two networks are communicating, which can prevent hackers in the network from accessing your network to the greatest extent. Refers to the combination of a series of components that are set up in different networks (such as a trusted intranet and an untrusted public network) or network security domains. It is the only entry and exit of information between different networks or network security domains. It can control (allow, deny, monitor) the information flow into and out of the network according to the security policy of the enterprise, and it has strong anti-attack capability. It is an infrastructure that provides information security services and realizes network and information security. Logically, the firewall is a separator, a limiter, and an analyzer. It effectively monitors any activity between the intranet and the Internet and ensures the security of the internal network.