SFC: Self-Describing Resilient Container File Format

This document specifies the Self-Describing Resilient Container (SFC) file format, a general-purpose binary container format designed for reliable transmission of arbitrary file data over unreliable, bandwidth-constrained, or asynchronous channels including physical media hand-carry, multi-session transfers, and heterogeneous delivery paths. SFC encapsulates any file or directory tree into independently addressable, self-identifying chunks. Each chunk carries sufficient metadata to identify itself and verify its own integrity in isolation. Full reconstruction additionally requires a Global Header; this distinction is made explicit throughout. This document defines a Core specification and five optional Profiles: Image (SFC/P1), Split Transport (SFC/P2), HTTP Hints (SFC/P3), Preprocessing (SFC/P4), and Directory (SFC/P5).