Security
16 posts under Security: attack prevention, backups, firewalls and certificate management. All from the field, newest first.
16 posts
WireGuard VPN Setup Guide: How to Configure the wg0.conf File
A step-by-step technical guide from WireGuard key generation to the Interface and Peer sections of wg0.conf, AllowedIPs and PersistentKeepalive settin
SecurityVPN Protocols Compared: WireGuard, OpenVPN, IKEv2 and L2TP
A technical comparison of the WireGuard, OpenVPN, IKEv2/IPsec and L2TP/IPsec protocols on speed, security, mobile roaming and getting through firewall
SecuritySetting Up the UFW Firewall on Ubuntu and Writing Rules
Setting up a firewall with UFW on Ubuntu: default deny/allow policies, the allow/deny/limit commands and the right order to avoid locking yourself out
SecurityWhat Makes a Password Strong? Entropy and Real Password Resilience
What password entropy is, how the character pool and length are calculated, brute-force attack scenarios and the passphrase approach to real password
SecurityHow to Check if a Link is Safe in 2026: URL Lookup, Phishing Detection and Website Safety
The 2026 guide to checking whether a link is safe: URL parsing, HTTPS/SSL inspection, WHOIS age, Google Safe Browsing, VirusTotal, urlscan.io, sandbox
SecurityBTK Lookup Guide: Website Access Blocks, Line and Operator Queries in Turkey
How to perform BTK lookups in Turkey: website access block status, banned site checks, line and operator queries, the 5651 law, USOM integration and t
SecurityBanned Websites in Turkey: Complete Blocked Sites List and Legal Guide 2026
Which websites are banned in Turkey? Law No. 5651, BTK and USOM decisions, how to query blocked sites, legal consequences of accessing them, and the t
SecurityHow to Get an SSL Certificate: Free vs Paid Options Explained
How and where to get an SSL/TLS certificate. Let's Encrypt, ZeroSSL, Sectigo and DigiCert compared. Installation with Certbot, acme.sh, cPanel and Ple
SecurityXSS Attacks and Defending with Content Security Policy (CSP)
Reflected, stored and DOM-based XSS explained, plus sanitization, output encoding and layered protection with Content Security Policy.
SecuritySQL Injection: How It Works and How Parameterized Queries Stop It
The mechanics of classic, blind, time-based and union-based SQL injection, plus how prepared statements and ORMs shut them down for good.
SecurityPassword Hashing: bcrypt, argon2id and scrypt Compared
Modern password hashing — bcrypt, argon2id and scrypt compared, salt, pepper, work factor tuning and Node.js / Python implementations.
SecurityOWASP Top 10 2026: Web Application Risks and How to Prevent Them
A walkthrough of the OWASP Top 10 2026 — Broken Access Control, Injection, Cryptographic Failures, SSRF and more, with practical mitigations.
SecurityOAuth 2.0 and OIDC: Secure Auth with the Authorization Code Flow
OAuth 2.0 and OpenID Connect — authorization code flow, PKCE, scopes, refresh tokens and a guide to integrating social login.
SecurityJWT Security Pitfalls: alg:none, Weak Secrets, JKU Attack and How to Defend
JSON Web Token security issues — alg:none, weak secrets, JKU/X5U injection, algorithm confusion and the controls that make JWT safe.
SecurityHTTPS and TLS 1.3: Modern Web Encryption and Performance
HTTPS and TLS 1.3 — handshake tuning, cipher suite selection, HSTS, OCSP stapling, an SSL Labs A+ score and performance.
SecurityMulti-Layer DDoS Protection with Cloudflare and Nginx
DDoS attack types (L3/L4/L7), Cloudflare WAF, Nginx rate limiting, Fail2ban and application-level defences — the full stack.
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