Glossary
Quick reference for SDC terminology used throughout the certification curriculum. Terms are organized alphabetically. Link directly to any term using its anchor (e.g., glossary.html#cuid2).
SDC RM component for authority assertions. Contains committer, proof, reason, committed, and pending fields. Used to record who asserted what and under what authority. Maps to W3C Verifiable Credentials 2.0.
SDC RM component for provenance and audit records. Contains system-id, system-user, location, and timestamp. Captures the chain of custody for every data interaction. Maps to W3C PROV-O.
SDC RM grouping component. Contains other components or nested clusters to form hierarchical structures. Used for workflow state machine trees and logical grouping of related data elements within a data model.
Collision-resistant unique identifier. Globally unique and immutable, assigned to every SDC component at creation time. Survives system migration, format transformation, and cross-platform exchange. The CUID2 is the component's permanent identity - different-language labels produce different components with different CUID2s.
The root node of every SDC data model. Contains governance slots for workflow, attestation, audit, participation, and other cross-cutting concerns. Every published data model has exactly one DMType at its top level.
W3C Data Privacy Vocabulary. Used in SDC for access control, retention policy, and consent management. Provides standardized vocabulary for expressing privacy-related information in data models.
The principle that derived dimensions cannot exceed the minimum of the foundational dimensions. For example, Level 4 Governance combined with Level 1 Schema Integrity yields a functionally Level 1 system. The weakest foundational dimension sets the ceiling for all derived dimensions.
The SDC six-dimension diagnostic framework. Three foundational dimensions (Schema Integrity, Constraint Enforcement, Semantic Identity) gate three derived dimensions (Provenance, Interoperability, Governance). Used to assess an organization's current data maturity and prescribe targeted interventions. See Module 4.
Model Context Protocol. Standard interface between AI agents and tools. Both sdcvalidator and sdcgovernance expose MCP servers, enabling AI agents to invoke validation and governance checks programmatically.
The principle that a component should contain only the attributes that distinguish it from neighboring concepts. Not maximal (everything possible), not minimal (bare minimum) - minimum knowledge captures exactly what is needed to differentiate the concept within its domain context.
The recurring revenue model where practitioners bill per schema change event rather than hourly or on retainer. Each time a client's data model requires updates - new fields, constraint changes, ontology additions - the practitioner performs a billable "touch." See Module 9.
SDC structural component that binds a Party to a data model in a specific role. Contains a performer (the Party), a function (what role they play), and a mode (how they participate). Used to model who is involved in a data event and in what capacity. Defined in the Reference Model as ParticipationType.
SDC structural component representing a person, organization, or agent involved in a data event. Contains a details Cluster for identity information and optional external references. Parties are referenced by Participations, Attestations, and Audit records.
W3C Provenance Ontology. Defines Entity, Activity, and Agent relationships for tracking data lineage. Used by sdcgovernance for provenance records in AuditType components.
The SDC4 base type system. All domain models restrict these types (XdString, XdQuantity, XdOrdinal, Cluster, DMType, etc.). The RM is never extended - domain models only restrict its types to add constraints. This is the foundation of two-level modeling.
Suite of AI agents for small and medium business data operations. Connects to local datasources (PostgreSQL, MySQL, SQLite, CSV), performs introspection, and builds SDC data models via SDCStudio. Runs locally with Ollama - no cloud API key required. The engine behind SDCforSMB.
Browser-based SDC data operations for small and medium business users. A Django web UI built over SDC Agents SMB, providing accessible data modeling and governance without requiring command-line tools.
Governance advisory engine. Evaluates data models against 24 standards, produces XACML decisions, generates hash-chained receipts, and exposes an MCP server for agent integration. Available on PyPI.
Cloud data modeling platform at sdcstudio.axius-sdc.com. Provides visual semantic data modeling with AI-powered processing. Upload data, generate SDC-compliant models, and publish outputs in 8 interoperable formats. See Module 2.
Structural validator for SDC data models. Performs XSD schema compliance checks with two-tier error classification (structural errors vs. advisory warnings). Exposes an MCP server for agent integration. Available on PyPI.
Architecture separating the reference model (stable, slow-changing types) from domain models (fast-changing, domain-specific restrictions). The reference model provides structural guarantees; domain models add business meaning through restriction, never extension. See Module 1.
OASIS eXtensible Access Control Markup Language. sdcgovernance uses XACML decision semantics for governance evaluations: PERMIT, DENY, INDETERMINATE, and NOT_APPLICABLE. Each decision is recorded as a hash-chained receipt.
XML Schema Definition. The W3C standard for defining the structure and constraints of XML documents. SDC uses XSD 1.1 to define data model schemas. sdcvalidator validates XML instances against their XSD schemas. Publication in SDCStudio includes automatic XSD generation and validation.
SDC extended datatype for ordinal and ranked values. Used in workflow state machines with ordered sequences where the relative position matters (e.g., severity levels, process stages, maturity levels).
SDC extended datatype for measured values with units and ranges. Carries unit of measure, magnitude, and optional range constraints (minimum, maximum) as part of the component definition.
SDC extended datatype for text values with optional constraints. Supports regex pattern matching, enumeration lists, and length restrictions. The most commonly used extended datatype in domain models.