Differences in security levels of firewall software and Practical Applications

This article is from scid.

As hackers flood, firewall software emerged to prevent malicious attacks. However, we should use the firewall software correctly to make it truly serve us.

The firewall defines the security level, in order to give different users different security control. However, many users do not fully understand this. To ensure security, they blindly adjust the security level to "High Security Level" and think that the higher the security level, the better. This is not the case. If your computer is too secure, you will find that online games cannot be started, in addition, the video program cannot access the online video files (which is a huge loss for ADSL users ). So what exactly does various security levels mean?

Low Security Level: computers will open all services, but computers on the Internet are prohibited from accessing file and printer sharing services. Applicable to users who provide services in the LAN. This is the security level with the highest degree of freedom, so it is limited to "network experts.

Medium Security Level: access to system-level services (such as HTTP and FTP) is prohibited ). Machines in the LAN can only access file and printer sharing services. Use Dynamic Rule management to allow port services opened by authorized programs, such as services provided by online games or video and voice calls. In addition, the security level is generally the default value because it can ensure that users who send and receive emails and transfer files can.

High Security level: the system will shield all ports that are open to the outside, prohibit access to the local machine to provide all services, block common trojan programs and attacks, and provide strictly controlled network access capabilities; applicable to users who only browse Web pages online. Of course you cannot play online games.

In addition, all security levels control the application's network access permissions.