Ideas, code & a curious mind

Practical thinking.
Useful software.

Notes on information security, Windows development and the mathematics behind everyday ideas.

A stepped pyramid of teal cubes. The sum from i equals zero to h of i squared equals one third h cubed plus one half h squared plus one sixth h.
AN INDEPENDENT TECHNICAL NOTEBOOKInformation securityWindows & developmentMathematics
A good place to start

Selected reading.

A few ideas worth a closer look.
From policy to the code that puts it into practice.

The notebook

Ideas worth sharing.

Articles, practical guides and working notes.
Follow your curiosity.

17 articles

Development updates

CI-TDF — Built on OpenTDF, Adapted for Practical Use

The first test version: readable manifests, encryption options and planned extensions.

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Development updates

ClassifyIt: Driving Persistent Data Security

A dated development update on OpenTDF, cryptographic protection and implementation plans.

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Information security

Zero-Trust Data Format Starts with X.509 Digital Certificates

The role of certificates in data protection, and an introduction to Certificate Creator.

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Information security

The Classification/Collaboration Gap

The complete case study on protection levels, release markings and external exchange.

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Perspectives

Trusted Data Format and Zero-Trust Data Format: Reality or just Theory?

Metadata, people and the practical challenge of making data-centric protection work.

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Information security

Classification Markings

A practical starting point for labels, handling rules and sharing across organisations.

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Information security

Case Study — Interoperability of Classification Markings

How can different organisations interpret the same information label?

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Windows & development

ADS — Alternate Data Stream

An introduction to NTFS alternate data streams and their limitations.

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Windows & development

Tutorial — Delphi — Shell Extension — Context Menu

From a COM object to a working shell extension: a five-part tutorial.

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Windows & development

Tutorial — Delphi — Shell Extension — Icon Overlay

Make file information visible directly in Windows Explorer.

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Windows & development

VirtualBox — Green Turtle — Windows 11

Collected notes on the green turtle indicator and Windows virtualisation.

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Mathematics

Calculate Square Numbers

A useful identity makes mental arithmetic a little easier.

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Mathematics

Sum of Quadratic Numbers

Explore the sum of the first n squares and the expression behind it.

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Windows & development

JSON

Objects, arrays and a readable way to exchange structured data.

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Windows & development

BIOS — Advanced Mode

Why firmware shortcuts need a hardware-specific context.

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Windows & development

Enable VT-x

The complete original virtualisation troubleshooting note.

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Information security

How Do You Classify Emails

The original email classification walkthrough with screenshots.

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From ideas to tools

Software with a purpose.

Practical projects shaped by development and information-handling problems.

01 / DEVELOPER TOOL

RegSvr ↗

Register COM DLLs from Explorer, inspect active shell extensions and make the development cycle easier to manage.

Windows ExplorerCOM / ActiveX
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02 / CERTIFICATE TOOL

Certificate Creator ↗

Create, sign, inspect and export X.509 certificates. A Windows application with RSA, ECC, CSR workflows and a local certificate store.

X.509 / PKIOpenSSL
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Original publications

From the archive.

Original product one-pagers, preserved as published. Current product details are at ClassifyIt.eu.

The person behind the notes

Hello, I’m
Ralf Ulrich Garbe.

I build software and share practical approaches to information security and development. This website brings together projects, tutorials and mathematical ideas worth exploring.

The common thread is simple: understand how something works, turn that understanding into something useful, and share what you learn.

Get in touch ↗

Let’s compare notes.

A question, an idea or feedback on a tutorial? I’d like to hear it.

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