Internet protocol (AODP)

Details and backgrounds

Phases of the AODP protocol

Every single purchase of an item carried out by a dealer's system (client) at a supplier's system (server) is carried out in a unique transaction, which at every time resides in one of five possible phases, controlled by client requests.

Starting with phase 1, a new transaction is opened. If it is accomplished without error the client can assume the requested digital item is available and may be delivered to the requesting dealer.

Phase 2 is supposed to assure that the physical file can actually be delivered. This is important in case the supplier's server has to create an individual file for every transaction. By signaling phase 2 the server guarantees that the file has been created and is ready to be delivered. This mechanism ensures that all multiple items of various suppliers in a consumer's shopping basket are ready for download before the consumer commences payment.

By requesting phase 3, the client commits the purchase and receives hereupon the download link (URL) from the server. The link is passed on to the consumer through the shop system. The download itself can now be started by the consumer.

Phase 4 starts after the first complete download was carried out. The client may check this at any time by sending a status request.

Phase 5 signals that the maximum number of downloads has been exceeded or the download time has expired. In case of a complaint by the consumer the dealer may send a reactivation request to the server, unlocking the download again, if the supplier allows it.

What about the accounting between supplier and dealer?

Accounting between supplier and dealer is done on their own discretion, as it is with physical products. This may take place on the fly while the transaction is executed or later on block, f.i. by normal invoicing. Accounting is actually no part of the protocol but may be automated in the transition to phase 3. As there is a unique numbering system for participants, items and transactions there is a common base for accounting data exchange. For instance every transaction can by identified on both sides by it's unique transaction ID.

AODP from a technological point of view

Technically, the internet protocol is based on existing internet standards. It uses XML-formatted messages which are exchanged via HTTP. However, AODP does not employ any HTTP specific functionality and is, thus, independent from its transport medium. For encryption/authentification SSL/TLS is used.