Message exchange on base of a blockchain-based layered architecture

Abstract

In this article, we propose an architecture that allows to exchange messages or data via a blockchain solution, while keeping the business process independent from the concrete blockchain. The project is the consequence of a need to have fast development of a blockchain based proof of concept that shows the feasibility of a business process, while knowing that in a future step the underlying blockchain solution has to be replaced for reasons of licensing or maximal data throughput. This is done by providing an architecture on base of layers, similar to the OSI-model, and encapsulates the used blockchain within a wrapper layer that covers all blockchain specific properties and only provides a transparent view on the reading or writing from and to the blockchain. The higher layers re-implement point-to-point communication and introduce confidentiality by the use of encryption techniques. The architecture has been tested and proven by implementing two different blockchain solutions that are shielded by specific wrapper layer implementations. This wrapper layer is responsible for the fragmentation of the sent data and their encapsulation into the concrete blockchain solution. The reconstruction of the data takes care of the data fragments being sent potentially out of order or being incomplete. A payload layer is introduced to provide point-to-point communication and to embed the main message inside a message structure. In collaboration with underlying layer it identifies for which message one is not the addressee and allow the underling layer to stop collecting unnecessary data. A crypto-layer finally provides ways of encrypting messages for one or many recipients. Having fixed layers not only allows to replace the underlying blockchain solution but also to extend or replace the other layers in case new security features or optimized protocols need to embedded. The proposed solution does not allow to use specific features like smart contracts and only provides undeniable tamper-proofed existence of a sent message.