Security

Table of Contents Introduction What Is a JWT? Why Algorithm Choice Matters Symmetric Algorithms (HMAC) 4.1 HS256, HS384, HS512 Explained 4.2 Implementation Example (Node.js) Asymmetric Algorithms (RSA & ECDSA) 5.1 RS256, RS384, RS512 5.2 ES256, ES384, ES512 5.3 Implementation Example (Python) The “none” Algorithm and Its Pitfalls Algorithm Negotiation and “alg” Header Common Attacks and Misconfigurations 8.1 Algorithm Confusion Attacks 8.2 Key Leakage & Weak Keys 8.3 Replay and Token Theft Best Practices for Selecting and Using JWT Algorithms Key Management Strategies Performance Considerations Conclusion Resources Introduction JSON Web Tokens (JWTs) have become the de‑facto standard for stateless authentication and information exchange across web services, mobile apps, and micro‑service architectures. While the token format itself is relatively simple—three Base64URL‑encoded parts separated by dots—the security of a JWT hinges almost entirely on the cryptographic algorithm used to sign (or encrypt) it. ...

Introduction JSON Web Tokens (JWT) have become a cornerstone of modern web authentication and authorization. From single-page applications (SPAs) to micro‑service architectures, JWTs provide a stateless, portable, and language‑agnostic way to convey claims about a user or system. Yet, despite their popularity, developers often misuse or misunderstand JWTs, leading to security vulnerabilities, scalability headaches, or unnecessary complexity. In this article we will explore JWT from first principles to advanced real‑world usage. You will learn: ...

Introduction Linux, like every modern operating system, revolves around the concept of processes. A process is an executing instance of a program, complete with its own memory space, file descriptors, and execution context. Whether you’re a system administrator tuning a production server, a developer debugging a multithreaded application, or a security analyst hunting for malicious activity, a solid grasp of how Linux processes work is essential. This article dives deep into the lifecycle of a Linux process, the kernel structures that represent it, the tools you can use to inspect and control processes, and the practical techniques for managing them in real‑world environments. By the end, you’ll be equipped to: ...

Introduction Secure Sockets Layer (SSL) and its successor, Transport Layer Security (TLS), are the foundational protocols that protect data in transit on the Internet. While end‑to‑end encryption is the ideal goal, many real‑world architectures rely on SSL/TLS termination—the process of decrypting TLS traffic at a strategic point in the network and forwarding the request as plain HTTP (or re‑encrypting it) to downstream services. In this article we will: Explain what SSL/TLS termination is and why it matters. Compare termination, pass‑through, and re‑encryption models. Walk through practical configurations for popular reverse proxies and load balancers (Nginx, HAProxy, Envoy, AWS ELB, and Kubernetes Ingress). Discuss performance, security, and operational considerations. Provide automation tips for certificate lifecycle management. Summarize best‑practice recommendations. By the end of the guide, you should be able to design, implement, and maintain a robust TLS termination strategy for modern microservice‑oriented environments. ...

Introduction The New Technology File System (NTFS) has been the default file system for Microsoft Windows operating systems since Windows NT 3.1, released in 1993. Over three decades, NTFS has evolved from a modest replacement for the aging FAT family into a sophisticated, high‑performance, and feature‑rich storage engine that powers everything from consumer laptops to enterprise data centers. In this article we will explore NTFS in depth: Historical context – why NTFS was created and how it has changed over time. Core architecture – the on‑disk layout, Master File Table (MFT), and metadata structures. Key features – journaling, security descriptors, compression, encryption, sparse files, reparse points, and more. Performance considerations – allocation strategies, fragmentation, and caching. Administration and troubleshooting – PowerShell/CLI tools, common errors, and recovery techniques. Real‑world use cases – when NTFS shines and where alternative file systems may be preferable. By the end of this guide, Windows administrators, developers, and power users should have a solid mental model of NTFS, be able to make informed decisions about its configuration, and possess practical skills for everyday maintenance. ...