Practical guides on network security, DNS, SSL, and web infrastructure. Written for developers, sysadmins, and anyone who wants to understand how the internet works.
How HTTPS encryption works, certificate types, and why every website needs SSL.
The Domain Name System explained — record types, resolution, caching, and security.
Step-by-step domain audit guide — or use the free Website Health Check for an automated report.
Types, uses, security risks, and how to discover all subdomains for a domain.
Request and response headers explained, including security headers every site needs.
How port scanning works, common ports, and legitimate uses for security auditing.
How IP-to-location mapping works, accuracy limits, and real-world use cases.
What dark web monitoring is, how data gets leaked, and how to protect your organization.
15-point security audit checklist for website owners and developers.
How server-side website screenshots work and why they matter for monitoring and QA.
Domain registration records explained — ownership data, privacy, status codes, and security research uses.
Why DNS changes take time, how TTL works, caching layers, and how to speed up global updates.
The future of web transport — how QUIC replaces TCP, 0-RTT connections, and what it means for performance.
Content Security Policy from basics to nonces and hashes — your strongest defense against XSS.
How DNS-based email authentication prevents spoofing and phishing — with a step-by-step DMARC rollout plan.
One-way hash functions, SHA-256 vs MD5, password salting, collision resistance, and key derivation.
How QR codes work, static vs dynamic, error correction levels, security risks, and use cases.
Epoch time, conversion to human-readable dates, timezone handling, and the Year 2038 problem.
Header.payload.signature structure, use cases, security pitfalls, and JWT vs session auth.
Syntax, data types, validation, common use cases, and how JSON compares to XML and YAML.
SPF, DKIM, DMARC overview, email spoofing prevention, and how to check your email auth.