What types of firewalls are there?

With the rapid development of the Internet, now every household has a computer and is connected to the network, in the network to bring us convenience at the same time, the drawbacks of the internet also slowly exposed, many people in the network will be intentional or unintentional attacks, which led to their own stored on the computer data by intruders stolen or lost, So the firewall is particularly important, the following for you to introduce the classification of firewalls.

Classification of firewalls

1. Packet filter Firewall

This is the first generation of firewalls, also known as Network Layer firewall, in each packet transmission to the source host will be in the network layer to filter, for illegal data access, firewall will choose to block and discard. This firewall connection can be through a network card that is a network card by the IP address of the intranet, and the public network of IP address and two network cards on a network card has a private network IP address, the other network card has the IP address of the external networks.

2. Status/Dynamic detection firewall

Stateful/dynamic detection firewalls, which can track network connections and packages through firewalls, so that the firewall can use a set of additional criteria to determine whether the packet is allowed or denied traffic. 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 accepts communications from the internal network-specific user application, and then establishes a separate connection to the public network server.

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