Automation processes in modern manufacturing generate a huge amount of data, which is used to guarantee stability and reduce the defect rate of the factory production lines. Collecting these datasets is not the problem; how companies protect them and ensure their integrity is. One of the low-cost possibilities is a blockchain technology.

The authors propose an interesting solution. It is a distributed machine-to-machine (M2M) communication protocol of the Internet of Things (IoT). This system “provides a public protocol [where] non-trust parties [can] participate and collect data in order to build [a] supply chain.” The system also supports complex tree-like workflows. All system details are given in section 4, where readers can find message creation flow, channel management, and back trace path covered. The process of message publishing on Tangle in IOTA is based on a Merkle tree. To create a hash tree (leafs, identifiers of the message owner), a seed is required. Then the “Merkle tree for [the] next message is created because the next root must be determined before its message has been published.” This requires seed sharing and channel switching, leading to merging.

A performance evaluation of the proposed system shows interesting results in storage overhead, time overhead, security, and compatibility, indicating that this could be a useful “distributed traceability system with blockchain technology.”