Documentation

Engineering knowledge is part of the infrastructure.

The lab maintains a structured documentation system so that architecture, implementation, validation, and operations remain traceable as the environment evolves.

Architecture overview

The environment connects a public domain, a dedicated mail hostname, cloud compute, Ubuntu, Nginx, TLS, Stalwart Mail Server, DNS records, and operational controls. Public web content is separated from administrative access, and the lab does not provide anonymous third-party relay capability.

DNS and authentication

The lab treats DNS as part of the security and identity architecture. Research includes address records, MX routing, SPF authorization, DKIM signing, DMARC policy, PTR records, forward-confirmed reverse DNS, certificate names, and consistency between the visible domain and the technical hostnames used during SMTP sessions.

Security model

The security model is based on least privilege, limited service exposure, encrypted transport, controlled credentials, system updates, reviewable logs, abuse prevention, and documented incident response. Security claims are not treated as complete without validation evidence.

Validation model

Validation is designed to answer whether a change produced the intended observable result. Examples include confirming DNS propagation, HTTPS certificate validity, hostname resolution, SMTP response behavior, authentication outcomes, firewall exposure, backup integrity, and recovery readiness.

Operational documentation

Operational material is organized around repeatable tasks and exceptional events: health checks, maintenance, certificate renewal, backup verification, restore testing, queue review, incident triage, change rollback, and lessons learned. Public summaries do not expose credentials, private configuration, or security-sensitive details.