Subnetting, VLANs, routing protocols, DNS, firewalls, and everything packets.
20 tutorials
Set up Cloudflare from scratch. DNS, SSL modes, CDN caching, WAF security, and performance optimization.
Set up Nginx reverse proxy for any backend. SSL, WebSocket, load balancing, and security headers.
Set up a SOCKS5 proxy server using SSH, Dante, or Docker. Configure browsers and apps to use it.
Set up and manage a Telegram MTProto proxy with multi-user support, per-user limits, bot control, and FakeTLS obfuscation — one-command install.
Master IPv4 subnetting from zero. Understand CIDR, subnet masks, and host calculations with real examples — then practice with our interactive calculator.
A complete walkthrough for deploying 3X-UI with every major protocol — VLESS, VMess, Shadowsocks, Reality, Trojan — plus CDN routing through Cloudflare and AWS CloudFront.
Understand Linux file permissions from scratch — read, write, execute, octal notation, chmod, chown, and when to use 755 vs 644 vs 600.
Your VPN might be leaking your real IP, DNS queries, or WebRTC data without you knowing. Here's how to test for every type of leak and fix them.
Understand how DNS translates domain names to IP addresses, the different record types, how caching works, and how to troubleshoot common DNS problems.
A practical regex reference with real examples — character classes, quantifiers, groups, lookahead/lookbehind, and ready-to-use patterns for common tasks.
Understand how SSL/TLS secures web traffic — the TLS handshake, certificate types, certificate chains, and how to diagnose common SSL errors.
Practical cron job examples for every situation — backups, monitoring, cleanup, SSL renewal, and more. Copy-paste ready with explanations.
Understand how JWT authentication works — token structure, the auth flow, access vs refresh tokens, common claims, and security pitfalls to avoid.
Understand the difference between public and private IPs, how NAT works, why your IP matters, and how to find and protect your IP address.
Stop emails from going to spam. Learn how to set up SPF, DKIM, and DMARC records to authenticate your email and prevent domain spoofing.
Understand how port forwarding works, when you need it, and how to configure it on your router for gaming, servers, cameras, and remote access.
Learn JSON from zero — syntax, data types, nested structures, how to parse it in code, and common mistakes to avoid.
Learn how to use WHOIS to find domain ownership, registration details, expiration dates, and how to investigate suspicious domains.
A technical breakdown of common VPN security flaws like IP, DNS, and WebRTC leaks, and the methodology used to test for them.
A guide to sending reliable transactional emails from a self-hosted app on Ubuntu using Gmail's SMTP server, msmtp, and proper SPF/DMARC configuration.