Tutorials

Articles and security guides about tutorials

• How to Tell If an IP Is Residential, Datacenter, CDN, or an Anonymizer Exit
  Identify whether an IP belongs to a home broadband line, a cloud datacenter, a CDN edge node, or an anonymizer exit — using ASN, rDNS, CDN fingerprints, and blacklists. Step-by-step on ipinfo.im.
  📅 2026-05-30
• What Is CGNAT? Why You Can Have a Public IP Yet Still Fail at Port Forwarding, and What 100.64.0.0/10 Means
  A practical guide to carrier-grade NAT, shared public IPv4 addresses, 100.64.0.0/10, double NAT, failed port forwarding, logging ambiguity, and geolocation side effects.
  📅 2026-04-28
• Why Do Website Logs Show 10.x.x.x or 192.168.x.x? How to Find the Real Client IP
  When logs keep showing 10.x, 192.168.x, or other private ranges, the usual cause is not that visitors are really internal. It is that your proxy chain did not correctly restore the real client IP.
  📅 2026-04-15
• What Is 169.254.x.x? APIPA, DHCP Failure, and Local Network Troubleshooting Guide
  169.254.x.x usually means a device failed to get a DHCP lease and fell back to an APIPA address. This guide explains the cause, symptoms, and troubleshooting order.
  📅 2026-04-15
• What Is 10.0.0.1? Router Login IP, Private Address Range, and LAN Usage Guide
  10.0.0.1 is usually not a public internet IP but a router login or default gateway address inside the private 10.0.0.0/8 range.
  📅 2026-04-13
• What Is a 192.168.1.* IP Address? Private IP Range List for 192.168.1.0 - 192.168.1.254
  192.168.1.* is not a public geo IP range. It is one of the most common private LAN IPv4 ranges, often used by home routers and local devices.
  📅 2026-04-07
• BGP Hijack and Route Leak Detection Guide: Validate Routing Anomalies with ASN, WHOIS, and Prefix Data
  A practical workflow for identifying BGP hijacks and route leaks with ASN data, WHOIS records, prefix ownership, and suspicious path changes.
  📅 2026-03-27
• Email Server Security Audit Guide: SSL Certificates & IP Blacklist Troubleshooting
  Why do your emails keep bouncing or landing in spam? This guide walks through the email delivery security chain — SMTP encryption, SSL/TLS certificate validation, and IP blacklist (DNSBL) checks — with practical audit steps and free tools you can use right now.
  📅 2026-03-19
• IP Lookup Guide: Use ipinfo.im to Check Geolocation, ASN, WHOIS, CDN and Connectivity
  A practical guide to ip lookup, ASN, WHOIS, CDN detection, ping, DNS and HTTP header checks with ipinfo.im for operators, developers and website owners.
  📅 2026-03-15
• Digital Shadows: How Advanced Forensic Traceback Unveils Your Identity Beyond IP Addresses
  Your IP is just the beginning. This guide deep dives into browser fingerprinting, WebRTC leaks, Canvas API, and ISP behavioral modeling to help you protect your digital identity against advanced forensic traceback.
  📅 2026-03-13
• IP Info Guide: What Is My IP Address and What Data Does It Reveal?
  Your IP address is more than just a number. Discover what information your 'IP Info' exposes—including true geolocation, ISP details, and ASN data. Learn how to prevent IP leaks and elevate your digital privacy in 2026.
  📅 2026-03-10
• What Is My IP? A Complete Guide to Finding Your IP Info
  Looking for your IP info? Whether you want to know 'what is my ip', check your geographic location, or find detailed IP information, this guide explains it all.
  📅 2026-03-07
• HTTP Security Headers Deep Dive: From CSP and HSTS to Complete Defense Configuration
  CSP, HSTS, X-Frame-Options explained with before/after attack surface comparison and ready-to-use Nginx configuration.
  📅 2026-03-05
• What is a DNS Leak? Why Incognito Browsing Isn't Enough
  Learn how DNS leaks expose your browsing history to your ISP, even when using incognito mode or basic proxy tools.
  📅 2026-02-27
• IPv4 vs IPv6: The Ultimate Comparison & What It Means for You
  A comprehensive guide on the differences between IPv4 and IPv6, exploring speed, security, and the future of the internet.
  📅 2026-02-25
• What Can Your ISP Actually See When You Browse?
  Think HTTPS makes you completely invisible? Your Internet Service Provider can still track surprising amounts of data. Learn how it works and how to protect yourself.
  📅 2026-02-24
• DNS Explained: Why It's the Biggest Blind Spot in Your Online Privacy
  Every URL you type triggers a DNS query — and by default, it's sent in plain text. This article breaks down how DNS works and how DoH/DoT encryption can plug this critical privacy gap.
  📅 2026-02-23
• Beginner's Guide: Understanding Subnet Masks and LAN in 10 Minutes
  What exactly is a subnet mask? Why does your local IP always start with 192.168? This article breaks down the fundamentals of Local Area Networks in plain English.
  📅 2026-02-21
• Home Router Security Guide: Preventing Public Exposure and Hacks
  Learn essential steps to secure your home Wi-Fi router, prevent unauthorized access, and protect your network from external cyber threats.
  📅 2026-02-20
• What is My IP Address? Complete Guide to Public IPs
  Understand what an IP address is, the difference between public and private IPs, and how to protect your online privacy.
  📅 2026-02-16
• Port Scanning Explained: From TCP Handshake to Security Assessment in Practice
  TCP handshake mechanics, SYN/Connect/FIN/UDP scan comparison, nmap port states, high-risk ports and defense recommendations.
  📅 2026-02-08
• The Real IP Behind CDN: Exposure Vectors, Detection Methods, and Origin Protection Guide
  7 ways origin IPs leak behind CDNs, detection methods, protection checklists, and CDN provider security comparison.
  📅 2026-01-22
• SSL/TLS Handshake Explained: From Key Negotiation to Certificate Chain Verification
  TLS 1.2 vs 1.3 handshake, certificate chain trust, DV/OV/EV comparison, SSL error fixes, and performance optimization.
  📅 2026-01-09
• Traceroute Deep Dive: From TTL Mechanics to Real-World Network Latency Diagnosis
  Starting from TTL mechanics, comparing ICMP/UDP/TCP probes, reading traceroute patterns, and systematic diagnosis with MTR.
  📅 2025-12-28