Security is the most important consideration for any secure network design. There are many ways to secure the network, and firewall techniques are one of the most important ways to implement network security.
The term firewall was in use as early as 1764 to describe walls that isolate the parts of a building most likely to have a fire (for example, a kitchen) from the rest of a structure. There are two types of firewalls: one is based on hardware, and the second is based on software. Hardware-based firewalls are dedicated hardware units used to protect a piece of network or segment, while software-based firewalls run on top of the operating system to protect host machines.
A firewall protection strategy ...
