Measure the test taker's understanding about the types of firewalls.

Comments: While the Internet brings us convenience, the drawbacks of the Internet are gradually revealed. Many people will be attacked intentionally or unintentionally when connected, as a result, the information stored on the computer is stolen or lost by intruders, so the firewall is particularly important. Next we will introduce the classification of the firewall.

With the rapid development of the INTERNET, every household now has computers connected to the INTERNET. While the network brings us convenience, the disadvantages of the INTERNET are gradually revealed, many people are intentionally or unintentionally attacked when they are connected to the Internet. As a result, information stored on the computer is stolen or lost by intruders. Therefore, firewall is particularly important, next we will introduce the classification of firewalls.

Firewall Classification

1. packet filtering Firewall

This is the first generation of firewall, also known as the network layer firewall. When each packet is sent to the source host, it is filtered at the network layer. For illegal data access, the firewall will block and discard it. This firewall connection can be achieved through a network card, that is, an Intranet IP address of the network card, a public IP address, and a private network IP address on two network cards, another ENI has an external network IP address.

2. Status/dynamic detection Firewall

Status/dynamic detection firewall, which can track network connections and packets through the firewall, so that the firewall can use a set of additional standards to determine whether the packets allow or reject communication. It applies some technologies to the communication using the basic packet filtering firewall.

3. Application proxy firewall

The application proxy firewall, also known as the application layer firewall, works on the application layer of OSI. The application proxy firewall does not allow direct communication between the networks it connects. Instead, it accepts communications from specific user applications on the internal network and then establishes separate connections with the public network server.

The above is the classification of firewalls. I believe you have some knowledge about firewalls. You should learn more about computers and networks so that you can encounter computer problems in the future, you can solve the problem by yourself.