An Imaging Document Source actor initiates the Provide and Register Imaging Document Set transaction. For each document in the Submission Set, the Imaging Document Source actor provides both the documents as an opaque octet stream and the corresponding meta-data to the Document Repository. The Document Repository is responsible to persistently store these documents, and to register them in the Document Registry using the Register Documents transaction by forwarding the document meta-data received from the Imaging Document Source Actor. [RAD-54, derived from ITI-15].