A firewall is a network security system that controls and filters network traffic, acting as a watchman between a private network and the public Internet.

They come in two broad categories:

• Software-based: installed on individual devices for protection

• Hardware-based: stand-alone devices that safeguard an entire network.

Firewalls have several types, each designed for specific security needs:

Packet Filtering Firewalls

Examines packets of data, accepting or rejecting based on source, destination, or protocols.

Circuit-level Gateways

Monitors TCP handshake between packets to determine session legitimacy.

Application-level Gateways (Proxy Firewalls)

Filters incoming traffic between your network and traffic source, offering a protective shield against untrusted networks.

Stateful Inspection Firewalls

Tracks active connections to determine which packets to allow, analyzing in the context of their place in a data stream.

Next-Generation Firewalls (NGFWs)

Advanced firewalls that integrate traditional methods with functionalities like intrusion prevention systems, deep packet analysis, and application awareness.