What Is a Firewall? Ports, Rules, and How Traffic Gets Filtered TL;DR — Key Takeaways A firewall is a security device or software that monitors and controls incoming and outgoing network traffic based on a predefined set of rules. Firewalls inspect packet headers — looking at source/destination IP addresses, port numbers, and protocols — to … Read more
Public vs. Private IP Addresses: What’s the Difference? Understand the two types of IP addresses every network uses, how NAT bridges them, and why the distinction matters for security, troubleshooting, and network design. TL;DR — Key Takeaways Your public IP address is assigned by your ISP and is visible to every server you connect to … Read more
Common Network Ports: What They Are and What They Do TL;DR — Key Takeaways Network ports are logical endpoints that allow multiple services to share a single IP address — think of the IP address as a building’s street address and the port number as the apartment number. There are 65,535 ports available, divided into … Read more