● Public technical archive

Open Systems Notes

Independent educational notes about DNS, TLS, HTTP/3, encrypted transport and resilient Internet infrastructure.

Modern network protocols

This archive documents how public Internet standards provide secure communication, service discovery and reliable data transfer.

DNS and certificate validation

Notes covering authoritative DNS, recursive resolvers, TLS certificates and authenticated encryption.

HTTP/3 and QUIC

Technical material about low-latency connections, multiplexed streams and modern transport design.