What kinds of firewalls are divided into

With the rapid development of the Internet, now every household has a computer and connected to the Internet, in the network to bring us convenience at the same time, the Internet's drawbacks are slowly revealed, many people in the Internet will be intentionally or unintentionally attack, Thus the data stored on the computer by the intruder is stolen or lost, so the firewall is particularly important, the following is to introduce the classification of firewalls.

Classification of firewalls

1. Packet filtering firewall

This is the first generation of firewalls, also known as the network layer firewall, each packet to the source host will be filtered at the network layer, for illegal data access, the firewall will choose to block and discard. The connection of this kind of firewall can pass a network card namely a network card is the IP address of the intranet, the IP address of the public network and two network card one network card has the IP address of the private network, the other NIC has the IP address of the external network.

2. Status/Dynamic detection firewall

Stateful/dynamic detection firewalls allow you to track network connections and packages through a firewall so that the firewall can use a set of additional criteria to determine whether the packet allows or denies communication. It does this by applying some technology 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 OSI application layer. The application proxy firewall does not actually allow direct communication between the networks it connects to. Instead, it is accepting communication from an internal network-specific user application and then establishing a separate connection to the public network server.

The above is the classification of firewalls, I believe that you have some knowledge of the firewall, we should know a lot about the computer, network knowledge, so that in the future encounter computer problems, they can solve.