DDEX has defined three different protocols by which various different entities (usually record companies or aggregators) can communicate ERN messages to their business partners. These are:
- Web services;
- Release-by-Release via SFTP; and
- Batched SFTP.
The order in which Releases need to be ingested in the first two cases is obvious from the order in which the information is being provided to the recipient. The order in which Releases need to be ingested using the batched SFTP approach requires additional explanation.
The batched SFTP protocol stipulates that the sender of the ERN messages should place all ERN messages, plus all the required Resource files, into a folder on the SFTP server. This folder is to be named after "the date and time of the batch folder creation" in the form YYYYMMDDhhmmssnnn.
It is this batch folder creation date/time, and not the creation date/time of the ERN files within the batches that determines the order in which a recipient needs to process the communicated Releases.