Application Gateway: The application gateway technique employs security methods applied to certain applications such as Telnet and File Transfer Protocol servers.

Packet Filtering: Firewalls filter packets that attempt to enter or leave a network and either accept or reject them depending on the predefined set of filter rules.

How Do Firewalls Work?įirewalls generally use two or more of the following methods to protect a network's perimeter: Techopedia Explains Firewallįirewalls are sometimes perceived as being old-fashioned because they are designed to protect a network from its perimeter, but in reality, they play an important role in Zero Trust Architectures (ZTAs). A firewall may be implemented through hardware, software or a combination of both.įirewalls at the perimeter of a network can be augmented by Zero Trust policies to ensure network access is granted appropriately and securely at every access layer of the OSI Model.

They work by enforcing security policies and are used to prevent malicious actors from gaining access to private networks connected to the Internet. Firewalls are used to block unauthorized access to or from networks that have different levels of trust.

What is firewall in networking