The Exchange System distinguishes between three types of file:

• FatturaPA file: a digitally signed XML that complies with the format of FatturaPA specifications. It may contain:
  • a single invoice (only one invoice body)
  • an invoice lot (several invoice bodies with the same heading).

  For the FatturaPA file signature, see the Sign the FatturaPA section.

• archive file: compressed file (exclusively in zip format) containing one or more FatturaPA files.

  The system processes the archive, checking the individual FatturaPA files contained within it and forwarding it to the addressee. In practice the FatturaPA files are treated as if they were transmitted individually.

  The archive file must not be signed but, instead, all the FatturaPA files in it must be signed.

• message file: an XML file compliant with a schema (xml schema) described by the file MessaggiTypes_v1.1.xsd which can be downloaded in the Exchange System documentation section.
  

  A message file can be:

  • a rejection notice: a message sent by the ES to the transmitter whenever the file transmitted (FatturaPA file or archive file) fails the checks provided for;
  • a metadata file: a file that the ES sends to the addressee, together with the FatturaPA file;
  • a delivery receipt: a message sent by the ES to the transmitter to certify that the FatturaPA file has been delivered to the addressee;
  • a failed delivery notice: the message sent by the ES to the transmitter to report that the FatturaPA file could not be delivered to the addressee;
  • a client outcome notice: a message that the addressee sends to the ES to report the acceptance or rejection of the invoice received; the report can be received by the ES within a deadline of 15 days;
  • a outcome notice: a message sent by the ES to the transmitter containing the decision reported by the addressee in the client outcome notice;
  • a client outcome rejection notice: a message sent by the ES to the addressee to report a situation where the client outcome notice is not admissible or non-conforming;
  • a deadline passed notice: a message sent by the ES to both the transmitter and the addressee, when 15 days have passed and no client outcome notice has been received, informing both parties that the period within which the system accepts the outcome notice message has passed;
  • a file undeliverable notice: a message sent by the ES to the transmitter when, after 15 days from the date of the failed delivery notice, it has not been possible to deliver in any way the FatturaPA file to the addressee.

• To view some examples of message files go to the Exchange System documentation section

  The Exchange System gives a different name to each message file type. For more information on naming message files see Annex B-1 of the document Technical specifications of the Exchange System - draft - pdf in the Exchange System documentation section.

  All messages produced and sent by the Exchange System, with the exception of the metadata file, are signed electronically with an advanced, XAdES-Bes electronic signature.

  The client outcome notice, the only notice sent by the addressee to the ES, may optionally be signed electronically, again in XAdES-Bes mode. For more information on the client outcome notice see the Communicating the outcome for the FatturaPA section.

There is a simplified flow which can be adopted by those who interact with the Exchange System in their roles as both transmitter and receiver through the same transmission channel; in this case the flow of messages undergoes changes to enable greater efficiency in the process of transmitting electronic invoices and the related notices.

More specifically:

• the FatturaPA file,
• the outcome notice to the transmitter

are not delivered because they are already available to the transmitter.

The process continues with the normal flow stages as if the files had been correctly transmitted.

The “Simplified Flow” option is associated with the registered channel for file transmission/reception; therefore Intermediaries intending to opt for the simplified flow may declare this when they register the channel in the Register the channel section.

NB: the “Simplified Flow” option is available for the Web-service, Domain Gateway and FTP transmission channels but not for the CEM and web transmission channels because these do not need prior registration with the Exchange System.