The ITMO Schema defines a standardized structure for Internationally Transferred Mitigation Outcomes (ITMOs) as W3C Verifiable Credentials. It combines established standards with domain-specific extensions to ensure interoperability and compliance with Article 6.2 requirements.
Key Components
Standards Compliance Built on W3C Verifiable Credentials and JSON-LD
Semantic Clarity Unambiguous term definitions via JSON-LD context
Cryptographic Proofs Ed25519-2018 suite for tamper-evident credentials
Data Provenance W3C PROV vocabulary for traceability
Core Structure Basic Structure
Python Implementation
{ "@context" : [ "https://www.w3.org/2018/credentials/v1" , "https://w3id.org/security/suites/ed25519-2018/v1" , { "itmo" : "https://w3id.org/article6/itmo-context.jsonld" , "prov" : "http://www.w3.org/ns/prov#" } ], "type" : [ "VerifiableCredential" , "ITMOCredential" ], "id" : "urn:uuid:<uuid>" , "issuer" : "did:ixo:entity:<issuer-id>" , "issuanceDate" : "<ISO-8601-date>" , "expirationDate" : "<ISO-8601-date>" }
JSON-LD Context The JSON-LD context provides semantic meaning to ITMO data, enabling unambiguous interpretation across different systems while maintaining data integrity and provenance tracking.
{ "@context" : { "@version" : 1.1 , "id" : "@id" , "type" : "@type" , "itmo" : { "@id" : "https://w3id.org/article6/vocab#" , "@prefix" : true }, "prov" : "http://www.w3.org/ns/prov#" } } Key Namespaces:
@version: JSON-LD versionitmo: Carbon market vocabularyprov: W3C provenance terms
{ "@context" : { "authorizationInfo" : { "@id" : "itmo:authorizationInfo" , "@type" : "@id" }, "ndcQuantification" : { "@id" : "itmo:ndcQuantification" , "@type" : "@id" }, "correspondingAdjustments" : { "@id" : "itmo:correspondingAdjustments" , "@type" : "@id" } } } Domain Terms:
Authorization details
NDC metrics
Adjustment records
{ "@context" : { "wasGeneratedBy" : { "@id" : "prov:wasGeneratedBy" , "@type" : "@id" }, "wasAttributedTo" : { "@id" : "prov:wasAttributedTo" , "@type" : "@id" }, "startedAtTime" : { "@id" : "prov:startedAtTime" , "@type" : "xsd:dateTime" } } } Tracking Terms:
Generation activities
Attribution entities
Temporal metadata
Credential Attributes { "credentialSubject" : { "itmo:authorizationInfo" : { "itmo:authorizationReference" : "AUTH-2024-001" , "itmo:cooperativeApproachDuration" : "2024-01-01T00:00:00Z/2024-12-31T23:59:59Z" , "itmo:expectedMitigationOutcomes" : { "2024" : 5000 }, "itmo:participatingParties" : [ "ZMB" , "CHE" ], "itmo:authorizedEntities" : [ "did:ixo:entity:project123" , "did:ixo:entity:verifier456" ] } } } NDC Quantification { "credentialSubject" : { "itmo:ndcQuantification" : { "itmo:sectors" : [ "Residential" , "Energy" ], "itmo:sources" : [ "BiomassFuelCombustion" ], "itmo:ghgs" : [ "CO2" , "CH4" , "N2O" ], "itmo:referenceLevel" : 1000 , "itmo:targetLevel" : 800 , "itmo:quantificationTonnesCO2e" : 200 } } } Corresponding Adjustments { "credentialSubject" : { "itmo:correspondingAdjustments" : { "itmo:singleYearTarget" : true , "itmo:multiYearTarget" : false , "itmo:emissionsTrajectory" : [ 1000 , 950 , 900 , 850 , 800 ], "itmo:annualAdjustments" : [ 40 , 40 , 40 , 40 , 40 ], "itmo:cumulativeAdjustment" : 200 } } } Validation & Proofs
from emerging import SchemaValidator # Validate against JSON Schema validator = SchemaValidator( "itmo-vc-schema.json" ) validation_result = validator.validate(credential) if not validation_result.is_valid: print ( f "Validation errors: { validation_result.errors } " )
from emerging import ProofGenerator # Generate Ed25519 proof proof = ProofGenerator.create_proof( credential, key_pair = issuer_key_pair, proof_type = "Ed25519Signature2018" , verification_method = "did:ixo:entity:123#key-1" ) # Add proof to credential credential.add_proof(proof) Developer Best Practices Interoperability
Use standard JSON-LD contexts
Implement full vocabulary
Support multiple proof types
Enable cross-registry exchange
Data Validation
Validate schema compliance
Check proof signatures
Verify credential status
Validate semantic constraints
Extension Points
Custom context terms
Additional proof methods
Enhanced provenance tracking
Registry-specific metadata
Implementation Guide
Create Credential
Initialize context and type
Add credential metadata
Populate subject data
Generate and attach proof
Verify Credential
Validate JSON-LD structure
Check schema compliance
Verify cryptographic proof
Validate business rules
Process Credential
Parse semantic data
Extract relevant claims
Process adjustments
Update registries
Next Steps 
