RESTChain: a Blockchain-based Mediator for REST Interactions in Service Choreographies

In inter-organizational contexts, different organizations cooperate exchanging information, to reach specific and shared objectives. The achievement of such interactions raises the need for a trusted communication environment to be used by the participants. This is a particularly relevant challenge when such interactions are specified in a peer-to-peer style, as in the case of Service Choreographies. Indeed, in such situations, the involved participants expect that all the interactions are performed abiding by the agreed specification. To support such a scenario, blockchain technology is gaining interest thanks to its security, trust, and decentralization characteristics. However, technological barriers still limit its adoption in real context due to the costly and time-consuming learning process. For this reason, we propose RESTChain, a general framework relying on blockchain technology enabling in an automatic way the interactions that take place among the participants in a service choreography. Starting from a choreography specification, the framework automatically derives a set of Mediators and a Smart Contract that coordinates the service interactions. In this way, each organization can communicate with the other services through the blockchain in a secure, auditable, and transparent manner.