Electronic invoices or bills are based on the Adobe PDF format. It is currently able to offer not only a true-to-layout reproduction, but also reproduces precisely the value-added services and logistics that are required for modern electronic processes, such as:
• Interactivity,
• User and access control,
• Signatures,
• Interactivity,
• Multimedia,
• 3D,
to name just a few features.

In addition, an intelligent PDF document permits every kind of data, based on XML, for example, to be transported. Therefore, in addition to the visible form of the bill, intelligent electronic billing can also contain the actual billing data - for easy further processing by the customer.

As a basis for XML data embedding, an XML diagram can be used as a supplement. The first standards have been created directly in the field of electronic billing, e.g. UBL 1.0 (Universal Business Language) as the approved OASIS standard (Organization for the Advancement of Structured Information Standards), see also http://www.oasis-open.org/committees/ubl.
An additional standardization example is the openTrans XML diagram. The openTRANS Initiative with leading German and international companies under the management of Fraunhofer IAO has set as its goal the standardization of business documents (contract, delivery note, bill, etc.) which is the foundation for electronic system-to-system communication. For additional information, please visit http://www.opentrans.org/

The actual PDF bill file, which should be used as the only document, can be generated from a
multitude of sources with regard to contents, even if these systems are unable to perform data
exchange amongst themselves. The document combines all sources, such as CRM systems for
the bill's header, billing systems with downstream sets of rules for the middle part as well as
additional systems that provide campaign-driven content, for example.

Architecture: Processing and preparation of the bill's contents