This specification conforms to FHIR®© R4

Message Identifiers and Timestamps

MessageHeader and Bundle Ids and Identifiers

A message contains at least two important ids and one identifier:

The Bundle.id is the unique id of a Bundle and is assigned by the FHIR framework. Each time a message is sent, the Bundle.id SHALL be changed to a new globally unique value. This SHALL be achieved by using a UUID. The Bundle.Id SHALL never be identical to a former sent Bundle.id.

The Bundle.identifier is also a unique identifier of a Bundle, but can be assigned explicitly by the sending application. The Bundle.identifier MAY be the assigned the same value as the Bundle.id.

The MessageHeader.id is the unique id of a MessageHeader and is assigned by the FHIR framework. Each time a new message is created, it SHALL be assigned a MessageHeader.id, that is globally unique. MessageHeader.id SHALL never be identical to a former sent MessageHeader.id.

When a receiver receives and processes the message, it SHALL respond with an Acknowledgement (a new message) with a new MessageHeader.id wrapped in a Bundle which also has a new Bundle.id. The response message SHALL also quote the request MessageHeader.id in MessageHeader.response.identifier so that the source system can relate the Acknowledgement to its request.

Message Timestamps

A message has several important timestamps:

In addition, the message MAY have additional timestamps in additional resources in the message. The meaning of these will depend on the message event.


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Version of this documentation

The version of this documentation is: Version 1.0.7 You can finde the release note of the version here.

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