Firewall Basics
Network Security 🌐 • Security+ 🏆
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Difficulty: free
Definition
Firewalls control network traffic to protect devices and services by allowing trusted connections and blocking unwanted ones.
Examples
- A home router blocks unsolicited inbound traffic from the internet while letting your laptop browse websites.
- An office firewall allows employees to use HTTPS and DNS but blocks remote desktop access from outside the company.
Overview
A firewall is like a checkpoint between networks. It examines network traffic and decides whether to let it through based on a security policy. Firewalls reduce the risk of attacks by limiting what can reach your systems from the internet and by controlling what internal devices can access outside. Even simple firewalls make a big difference by enforcing a default deny stance for risky or unnecessary connections.
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