Firewalls

Overview

A firewall is a classic example of a security device that organizations rely on for protection from network-based attacks.

Where to install them

Firewalls can be utilized in the following locations:

• They’re commonly installed at the perimeter that separates an internal network from the internet.

• They can also be installed on the internal network to provide additional protection to network segments that host sensitive resources like employee or credit card data.

How they work

The internet perimeter is the front line, and the firewall installed at this location routinely observes and blocks scans and other attacks from getting through. Firewalls, however, have evolved to do more than control the flow of individual packets. Now the term firewall has been extended to appliances that specifically protect databases, web applications, and solutions that provide several different forms of network-based protection.

Network firewall

A network firewall limits access to devices, other networks, and segments of a network. It inspects the attributes of individual packets and can analyze them in different ways. It can also operate at different network layers.

Layers of the network packet

Billions of packets may traverse an organization’s network every day, and each packet has several properties and layers. The open systems interconnection( OSIOSI ) model was created to provide a logical view of the different layers that make up a network packet.