BotNet News

Your source for Online Security News


A firewall is a security system that monitors and controls network traffic based on predefined rules. Firewalls are often used in office networks, in-home devices, and other locations to protect against threats and stop hackers from gaining access to your data.

How Firewalls Work

A packet-filtering firewall, also known as stateless inspection, operates at the OSI network layer and offers basic filtering based on IP addresses, ports, and packet protocols. It checks all individual data packets sent across a network, re-approving previously accepted connections with each new one.

Another type of firewall, a circuit-level gateway, operates at the session OSI layer and monitors TCP (Transmission Control Protocol) handshakes between local and remote hosts to quickly approve or deny traffic without consuming significant computing resources. However, it does not inspect packets to determine whether they contain malware or legitimate traffic requests.

Proxy firewalls, also known as application-level firewalls, combine stateful inspection with packet-filtering and offer a more granular level of protection than static-packet filters alone can provide. They also read and filter application protocols, a unique feature that was developed in response to attacks against web servers.

For the best cybersecurity protection, administrators should choose a firewall based on its capabilities and its fit with their needs. Admins can deploy software or hardware/firmware firewalls, both of which require constant maintenance to stay current with the latest vulnerabilities. Personal and home users can update their firewalls quickly and safely, whereas larger organizations may need to check compatibility and configure their networks first before installing patches.