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Dmark
Understand your email authentication. Dmark helps you interpret your domain’s SPF, DKIM and DMARC records and identify what needs a closer look.
Explore Dmark
Independent Icelandic technology company
Software and security.
Kastro develops software focused on cybersecurity and privacy. It is the company behind dmz, alongside tools for email authentication and technical investigation.
Andri Pétur HafþórssonFounder and operatorandri@kastro.is
A Kastro product↳ dmz.is
dmz. By Kastro.
The service is in preparation. Explore its functionality, measurements and limitations at dmz.is.
dmz.is · Service in preparationA Kastro product
dmz.
// Icelandic data minimisation for AI
Data minimisation for AI.
dmz is designed to detect and mask selected direct identifiers, such as names and Icelandic ID numbers, before text reaches an AI model. When unchanged placeholder tokens return in the response, the original values are restored.
Shield · synthetic dataOn device
01 · You writeOn device
Draft a reply for Arna Jónsdóttir, ID 140182-8858. Send to demo@example.com.
Masking identifiers does not automatically make text anonymous. Context can still identify a person.
More about dmz →Service in preparation
More tools from Kastro.
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Lookup
Public information about domains and IP addresses in one place. Look up DNS records, WHOIS information, TLS certificates and email authentication.
Open Lookup
Andri Pétur Hafþórsson
I’m Andri. I run Kastro.
I develop the products and handle service and security enquiries. My background is in systems administration, infrastructure, cybersecurity and software development.
Kastro is a small, one-person business. You speak directly with the person responsible for the work.
Andri’s personal credentials and experience
ISO/IEC 27001 · ISO/IEC 27701 · ISO/IEC 42001. Lead Auditor Fellow at Mastermind Certifications.
Revamped RVX’s infrastructure, designed its new office around TPN Gold requirements and led the company through certification.
These credentials and experience belong to Andri. They do not constitute certification of Kastro or its products.
Security reports: andri@kastro.is
Advice and implementation.
Alongside product development, I take on defined projects for businesses. Scope and timing are agreed before work begins.
New client work: Limited availability.
Kastro Vefir
Website design, redevelopment and maintenance. Explore projects, pricing and what is included.
Kastro VefirTechnical consulting
Help choosing systems, planning infrastructure and implementing technical changes.
Technical consultingSecurity and audit preparation
Review access, configurations and evidence, with clear priorities for improvement.
Pricing, scope and monthly care are available on the Kastro Vefir page. Explore pricing and scope
Get in touch directly.
andri@kastro.isQuestions about dmz, other products or a project? Send me a message. I take on defined projects by agreement. Product enquiries are welcome.