[Term of the Day]: Firewall

Term of the Day

“Firewall”

Definition — What is a Firewall and it does in a network?

A firewall is a software or hardware or can be a combination of both that acts as the first line of defense in a network. It monitors incoming and outgoing network traffic and decides whether to allow or block specific traffic based on a defined set of security rules.

It prevents unauthorized access to a network by establishing a barrier between secured and controlled internal networks that can be trusted and untrusted outside networks, such as the Internet.

There are several types of Firewall and the main types are:

Packet-Filtering Firewall that examines packets in isolation and does not know the packet's context.

Proxy Firewall (aka application-level gateway) inspects packets at the application layer of the Open Systems Interconnection (OSI) reference model.

Stateful Inspection Firewall examines network traffic to determine whether one packet is related to another packet.

Next-Generation Firewall (NGFW) uses a multilayered approach to integrate enterprise firewall capabilities with an intrusion prevention system (IPS) and application control.