As described here, the idea of Dibichain is to provide and consume product information in an anonymous fashion. To do so, the Dibichain system uses an EVM compatible Smart Contract as an event bus to broadcast two types of events, the new product and product details request event. Every participant (company) is able to issue and listen to these two event types. If a company decided to broadcast a new product, it can do so by issuing a transaction to the event bus contract with public available, non critical information. The company is also required to provide a hash of the full product information data set, so that a product details requester is later able to verify the received product details. It should be mentioned that no company related information is required to broadcast a new product, so that the product issuer stays anonymous.
To reduce complexity for the Dibichain demonstrator, an operator is installed that handles transaction issuing for the companies. Listening to events is done by the companies themself, since there is no wallet and funds handling required. The operator also acts as a central point for company-to-company messaging.
When a company receives a new product event, it can decide if it is interested in the details and issue a product details request via the operator. To do so, it first generates a new asymmetric key pair and adds the public key to the request along with the unique identifier of the product the company is interested in. After receiving such an event, the company that issued the new product event again decides if it wants to response to the request or not. If it declines the request times out. If it decides to answer, it encrypts the full product details information including the associated documents with the provided public key and sends the encrypted data to the operator. The requesting company polls the operator for answer messages of its requests. After receiving the encrypted data message from the provider company the operator forwards the message to the requester company in the next answer message poll.
The requester company then decrypts the product details and validates the data by comparing a self-created hash with the hash stored in the new product event. If everything checks out, the request company received the complete product information set from the provider company in an anonymous way.
Even though the above described mechanism works entirely in a machine-to-machine way, a company frontend is provided to showcase the flows.
The following diagram shows a detailed sequence diagram of the flows needed to enter a product including its documents to the Dibichain demonstrator up to the point where one product is send from company A to company B.
