6.1 Introduction

This Clause contains an overview of the three messages in the Standard for requesting and communicating Links between Resources and Musical Works in a tabular form. The full technical specification is included in the XML Schema files accompanying this standard.

The hierarchical structure of the messages is provided through indentation. On the MessageHeader for example, the PartyName is a child of Sender. Thus, a Sender contains a PartyName (plus a PartyId). A second example from the MessageHeader is the MessageAuditTrail that contains MessageAuditTrailEvents which, in turn, contains a MessagingPartyDescriptor and a DateTime element. All elements that have sub-elements are printed in bold. The MessageAuditTrailEvents element also shows a second structural feature of the MessageSummary: the cardinality. In the case of MessageAuditTrailEvents the entry "1-n" means that each MessageAuditTrail contains one or more MessageAuditTrailEvents.

Other possible cardinality entries are: "1" (for: exactly one), "0-1" (for: none or one) or "0-n" (for: none to multiple). Elements shown in italics are represented in the XML Schema as XML Attributes.

In addition to the tabular description of the messages, which should always be read in conjunction with the XML Schema files, additional conformance rules, which go beyond XML Schema validation, are provided where necessary. The general conformance rules for all messages within this Standard are provided in Clause 6.3.

The syntax as well as the semantics of the various elements in the message is provided in Clause 6.4. They are taken from the current version of the DDEX Data Dictionary as defined through, and maintained in accordance with, the DDEX Data Dictionary Standard.