Writing
Notes on AI, cybersecurity, Zero Trust and media forensics by Shariar Kabir, researcher at the University of Portsmouth.
- What Is RAG? Retrieval-Augmented Generation Without the Hype
What RAG (retrieval-augmented generation) actually does, why LLMs hallucinate without it, how chunking and embeddings work, and where RAG quietly fails.
- How to Spot AI-Generated Images: A Forensics Field Guide
How AI-generated image detection actually works: camera fingerprints, frequency artefacts, CLIP embeddings, and why your eyes are the least reliable tool.
- Overfitting Explained: Your Model Aced the Exam and Failed Life
Overfitting explained in plain words: overfitting vs underfitting, data splits, why rising validation loss is the tell, and how regularisation stops it.
- Docker Security Hardening Checklist: 12 Fixes That Matter
A practical Docker security hardening checklist: non-root users, read-only filesystems, dropped capabilities, no Docker socket, digests and limits.
- Machine Learning for Intrusion Detection: What Actually Works
How machine learning intrusion detection works: flow features, random and isolation forests, dataset pitfalls, class imbalance, drift and SIEM deployment.
- Data Leakage in Machine Learning: The Bug That Makes You Look Brilliant
Data leakage in machine learning explained: target leakage, train/test contamination, time-series leaks and duplicates, and how to catch the bug early.
- LLM Security: The OWASP Top 10 for LLM Applications Explained
A developer's walk through the OWASP Top 10 for LLM applications: prompt injection, excessive agency, data poisoning, model theft, and mitigations that actually work.
- Accuracy vs Precision vs Recall: Why Accuracy Lies to You
Accuracy vs precision vs recall explained with a confusion matrix: why 99% accuracy can be useless, what F1 measures, and when each metric matters.
- Federated Learning Explained: Privacy-Preserving ML
Federated learning explained: FedAvg, why shared gradients leak, differential privacy, secure aggregation, and the real costs in healthcare and edge networks.
- How to Read a Machine Learning Paper Without Being Fooled
How to read a machine learning paper efficiently and critically: the three-pass method, baselines, leakage, ablations, red flags and a checklist to keep.
- Machine Learning for Early Dementia Detection: A Careful Guide
How machine learning for early dementia detection works: the data, why it is a screening aid not a diagnosis, patient leakage, SHAP and the ethics.
- How Transformers Work: Attention Explained for Busy People
How transformers work, without the maths: tokens, embeddings, attention with queries, keys and values, multi-head attention, and why it costs so much.
- Adversarial Examples: Fooling Image Classifiers With Noise
Adversarial examples explained: FGSM intuition, why tiny perturbations flip predictions, patch attacks, and what the defences mean for deepfake detectors.
- Explainable AI with SHAP and LIME: Defending a Model's Decision
Explainable AI for people who must defend a model's decision: feature importance, SHAP, LIME and Grad-CAM, and the pitfalls that make an explanation misleading.
- AI Doesn't Steal Jobs, But It Might Roast You: LLMs at Work
How to use LLMs at work without leaking data or shipping hallucinations: what they are good at, prompt injection, verification and accountability.
- Diffusion Models Explained: How AI Image Generators Actually Work
Diffusion models explained: forward noising, learned denoising, text conditioning and latent diffusion turn static into images, and why they leave traces.
- Digital Forensics Basics: Hashing and Chain of Custody
Digital forensics fundamentals: bit-for-bit imaging, write blockers, SHA-256 hashing, chain of custody, order of volatility, why evidence gets thrown out.
- Transfer Learning Explained: Fine-Tuning CNNs on Small Datasets
Transfer learning explained: how to fine-tune ImageNet-pretrained CNNs on small datasets, which layers to freeze, and when domain shift breaks it.
- The Day My Python Script Went Rogue: Safe Automation Rules
How to write safe Python automation scripts: idempotency, dry-run flags, confirmations, explicit paths, logging, retries with backoff and cron file locks.
- TLS 1.3 Handshake Explained: What Happens Before HTTPS
What actually happens in a TLS 1.3 handshake: ClientHello, ECDHE key exchange, certificate chains, forward secrecy, why it beats TLS 1.2, and mistakes to avoid.
- What Is a Cyber Range? Why Hands-On Labs Beat Slides
What a cyber range is, the main types of hands-on security lab, the components that make one work, and how to design and assess a good lab exercise.
- Python Virtual Environments: Stop Saying It Works on My Machine
Why global pip installs break, how to make a Python virtual environment in three commands, and how to pin dependencies so research code runs again.
- ML Models Are Like Toddlers: Why Training Is Unstable
Why neural network training is unstable: learning rate, exploding gradients, overfitting, early stopping, dropout, batch norm, LR schedules and seeds.
- When You Docker Compose Into Chaos: 8 Pitfalls and Fixes
Docker Compose pitfalls that take labs down at 2am: depends_on and healthchecks, DNS by service name, volumes, .env precedence, latest tags and logs.
- CTF for Beginners: How to Start Capture The Flag
How to start CTF competitions as a beginner: categories, jeopardy vs attack-defence, legal practice platforms, first tools and how to write up solutions.
- How I Taught My Neural Network to Fear Cats: Class Imbalance
Why accuracy lies on imbalanced data, and how to fix class imbalance in image classification with confusion matrices, class weights and stratified splits.
- Password Hashing Explained: Why 'We Encrypt' Is a Red Flag
How password hashing works, why MD5 and SHA-256 are the wrong tools, and how salts, Argon2id, peppers and rate limiting actually protect your users' passwords.
- Wireshark Packet Capture Basics: Reading Your First PCAP
Wireshark packet capture basics: capture vs display filters, the TCP three-way handshake, following streams, finding retransmissions and tshark.
- Zero Trust, Zero Friends: My Journey to Cybersecurity Paranoia
Zero Trust Architecture explained: never trust, always verify, NIST SP 800-207 components, micro-segmentation, and why the VPN perimeter model failed.
- Git for Research Code: Commit Like Someone Will Read It
Git for research code: small commits with real messages, branches for experiments, tags for the paper version, and a .gitignore that keeps secrets out.
- Penetration Testing Methodology for Beginners: Scope to Report
A beginner's penetration testing methodology: authorisation and scope first, then recon, enumeration, exploitation and the report that is the product.
- DeepGuard: AI-Powered Image Authentication for a Synthetic World
DeepGuard is a state-of-the-art forensic AI system designed to detect AI-generated images with high accuracy