How Firewalls Analyze and Filter Packets
Firewalls are the digital bouncers of your network — deciding which traffic gets in, which gets blocked, and what needs further inspection. Whether you're using a personal computer, managing a business network, or securing cloud infrastructure, firewalls are essential to protect against unauthorized access and cyber threats. But how do firewalls actually work ? Let’s break down how they analyze and filter packets to keep your system safe. What Is a Firewall? A firewall is a security device (hardware or software) that monitors and controls incoming and outgoing network traffic based on predetermined rules. It acts as a barrier between a trusted internal network and an untrusted external network , like the internet. What Are Packets? Before diving into filtering, it’s important to understand what a packet is. A packet is a small chunk of data sent over a network. Each packet contains: Header – Metadata like source IP, destination IP, protocol, port number, etc. ...