Distributed Decision of Trust

We live in an age where most, if not all of us use interconnected technological devices all day, everyday. The interconnectivity is sometimes established by trusted third party servers, and sometimes established in a completely peer-to-peer way thanks to the advanced technologies like bluetooth and wi-fi. While sometimes these devices are completely controlled by us, sometimes they take decision on behalf of us by using both their local knowledge-base and the information gathered from the others. When we say that an intelligence makes a decision, it must be understood in a broad sense. It can be a system that makes recommendations to it’s owner, or a system that organizes a trip for it’s owner and makes the necessary reservations, or a system that buys and sells energy from and to it’s neighbors. The examples can be extended. But, how can an such an artificial intelligence take its decisions with trust? How can it know that the information declared by others are trustable? The answer to these questions is “by using the blockchain technology”.

The blockchain technology was born only around a decade ago with the arrival of Bitcoin [Nakamoto2008]. Now known by everybody, Bitcoin, is the core of blockchain systems; decentralized transactional systems that are based on blockchain protocols. In it’s broadest sense, a decentralized transactional system is a distributed, social and technical system that processes and stores information flow carried out between two or more parties (i.e., transactions) and guarantees the consistency and trust. Traditional decentralized transactional systems guarantees trust relying on trusted participants. Blockchain systems, however, operate in a completely peer-to-peer way where all participants perform transactions in-between without neither needing to trust each other nor having a trusted third party. Each participant validates the diffused data, and keeps a replica of the entire blockchain. It is a very attractive technology since it guarantees the immutability of the information stored and thus provides an auditable history. Thanks to this, a distributed artificial intelligence can take decisions with trust.