General explanation of ECM

Each part of the ECM is guided by a set of overarching principles that complement the technical specifications and support the structured communication of defined datasets:

Precision in cluster definition

All parts of the ECM define entity clusters with a high degree of precision—particularly in relation to the set of all elements that are used to characterize a cluster. This includes unambiguous communication of required data points, choreography, and—critically—the roles and permissions associated with who can declare, modify, or withdraw a cluster.

Bi-directional communication

All messages relating to clusters support bi-directional communication. Each exchange occurs between two parties - a sender and a recipient - who may each hold differing representations of a cluster for the same musical work or ‘root^[1]’ sound recording.

Stateless and time-bound messaging

Given the dynamic nature of some clusters, each message represents a statement of truth at the moment of transmission, in line with the stateless messaging model adopted across all DDEX standards. Specifically, the MusicalWorkClusterNotification message conveys a snapshot in time and does not assert whether a given cluster is definitively correct or incorrect.

Verification of the accuracy, completeness, or legitimacy of cluster information is outside the scope of this standard and shall be addressed through separate governance, contractual or operational processes.

Full cluster in response messages

Response messages always contain the complete cluster as known to the sender. This ensures consistency with the stateless design model and supports downstream processing without requiring context from previous messages.

Confidence signalling

Each message should include an explicit confidence signal from the sender regarding the inclusion of each sound recording in the cluster. This enhances trust, facilitates auditing, and supports data quality evaluation.

Blueprint for broader standards integration

Each part of the ECM will also serve as a blueprint for data requirements that may be considered for integration into other DDEX standards.

Information on the relationship between cluster requests and cluster notification, and the use of cluster IDs can be found here.