Technical articles on DNS, networking and IP infrastructure
Reverse DNS and PTR Records Explained (and Why Mail Servers Need Them)
SPF, DKIM and DMARC Explained: How to Check Your Email DNS Records
How Accurate Is IP Geolocation? Why Your IP Shows the Wrong City
What Is an ASN? How to Find Who Owns an IP Address
How to Check If a Website Is Blocked in Iran
How to Check If a Website Is Blocked in China (and What DNS Poisoning Looks Like)
Understanding DNS Propagation: How It Works and Why It Takes Up to 48 Hours