JSON-LD ⊂ SPXI ⊄ Schema: The Operational Depth of the Semantic Packet Protocol

EA-SPXI-15. JSON-LD is a proper subset of SPXI. SPXI is not a subset of Schema. This document specifies the operational depth that distinguishes SPXI from schema markup: a five-layer stack of measurement, compression architecture, protection, dispersal, and durability testing. Five layers: (I) Measurement: γ scoring, Drowning Test, Density Score (Δ), Semantic Decay Delta (SDD), Provenance Erasure Rate (PER). (II) Compression: entity-definition packets, disambiguation matrix, three-tier compression (full/canonical/kernel), holographic kernels, citation-density engineering. (III) Protection: Semantic Integrity Markers (SIMs), integrity locks, Sovereign Provenance Protocol, supraliminal inscription. (IV) Dispersal: DOI anchoring, multi-surface inscription, retrocausal canon formation (σ_RCF). (V) Durability: γ re-scoring, SIMSR, back-projection testing, competitive monitoring. JSON-LD completes one cell of the operational stack. SPXI operates across all five layers. The difference is the difference between a single seal at the gate and the full protocol of ascent. Grounded in Three Compressions v3.1 (DOI: 10.5281/zenodo.19053469): every semantic operation is a compression operation; the decisive variable is what the compression burns. SPXI controls what survives. Technologies drawn from the Compression Arsenal (EA-COMPRESSION-ARSENAL-01). Hex: 06.SEI.SPXI.15 | spxi.dev | Semantic Economy Institute