In Bitcoin, to independently verify whether new transactions are correct or not, a type of a node called “Full Node” has to hold the whole of historical transactions. The transactions are stored in ledger called “Blockchain. ” Blockchain is an append-only data structure. Thus, to operate Full Nodes, the required storage capacity would grow too large for resource-constrained devices. Due to the limitation, the existing lightweight node scheme is that a node relies on other Full Nodes. In this thesis, to reduce storage capacity with keeping the independence of each node, we propose a storage load balancing scheme “KARAKASA” using Distributed Hash Table (DHT). In KARAKASA, nodes distributedly keep the whole blockchain among DHT networked nodes. We evaluated KARAKASA from the view of storage capacity and independence. As a result, a node in a cluster does not need to trust other nodes. We concluded that nodes in a DHT cluster can behave like Full Nodes without holding the whole blockchain.

In recent years, manufacturing using digital machine tools called digital fabrication has spread rapidly. Unlike concentrated mass production by existing manufacturers, a flaw in which each individual produces a small amount in a dispersed manner is also being developed. The 3D model to be the design drawing is used by those made by individuals or those made by duplicating or modifying things published on the Internet.However, it is difficult to clarify the location of production or intellectual property unless information such as the design drawing of the product and the manufacturer is preserved. In order to clarify the location of manufacturing responsibility and intellectual property right, it is necessary to clarify “Openness” that anyone can refer to data, “Traceability” of information linked to products, “Integrity” which is not tampered is required. Fujiyoshi et al. Achieved the linking of information and products by embedding RFID in the product for product management, The above problem is still unresolved.Therefore, in this research, I thought that by using Blockchain technology, by saving manufacturing information on the open ledger, it is possible to satisfy the necessary conditions and clarify the location of manufacturing responsibility and intellectual property right. The Blockchain technology is a system that secures the integrity of data by forming a distributed open ledger on the P2P network and mutually verifying input data and preserving it.In order to verify this method, I implemented the system save manufacturing information on Blockchain by making a single board computer control a 3D printer a Blockchain node.Using this system, we verified the above items of “Openness”, “Traceability”, and “Integrity”, so that the system tracks manufacturing information on products and, It is possible to clarify the manufacturing responsibility and the location of the intellectual property right when the manufacturer himself is the producer of the design drawing.Based on the results of this research, it is possible to clarify the manufacturing responsibility and the location of the right also in personal manufacturing. This system is a disincentive not to manufacture at a quality that does not cause accidents that the manufacturer is responsible for. Moreover, by applying this method and managing the distribution of the design drawing on Blockchain, it is possible to manage the product manufactured by the 3D printer as intellectual property.