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The IP & Network Blog
Real answers to real questions about IPs, VPNs, DNS, and everything in between.
HTTP Headers Explained: What Every Site Knows About You Before You Click
Every web request you make ships with a small pile of metadata your browser sends automatically. Most people have no idea what is in there. Spoiler: a lot more than you would expect.
Port Scanning Explained: What Open Ports Actually Reveal About a Server
Open. Closed. Filtered. Three little words that decide whether a server is exposed, locked down, or hiding behind a firewall. Here is how port scanning actually works and what each result means.
SSL Certificate Expiration: Stop Your Site From Going Down at 3 AM
Every SSL cert has an expiration date. Miss it and your site goes dark, your APIs stop working, your mobile app crashes. With 47 day certs coming, you cannot wing this anymore.
Subnet Mask Explained: CIDR, /24, /28 in Plain English
Subnet masks look like math homework but they are really just a way to split networks into smaller pieces. Here is the no jargon walkthrough that finally makes /24 and /28 make sense.
Is My IP Blacklisted? How to Check and What to Do About It
A blacklisted IP can get your emails rejected, access blocked, and services denied. Here's how to find out if yours is on a list and how to get off it.
IPv4 vs IPv6: What's the Difference and Do You Have Both?
The internet ran out of IPv4 addresses years ago. IPv6 was supposed to fix everything. Here's what actually happened and whether you're running both right now.
What Does Your IP Address Actually Reveal About You?
Your IP address gives away more than you think. City, ISP, whether you're using a VPN, and sometimes your employer. Here's the full breakdown.
How to Check if Your DNS Is Leaking (And Why It Matters)
A DNS leak silently sends your browsing history to your ISP even when your VPN is on. Here's what it is, how to find out if you have one, and how to stop it.
What is a VPN Leak and How Do I Fix It?
Your VPN might be on and still leaking your real IP. Here's what a VPN leak actually is, why it happens, and how to test and fix it in minutes.
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