A Dynamic Trust Model for Blockchain-Based Supply Chain Management Networks

A blockchain architecture lacks central authority, so control of single unit cannot be implemented in this structure. All the actions that happen involve one or another single node which is part of the network. The main objective of this work is to implement a dynamic trust model for a blockchain network for each node connected. The actions that are performed by the nodes while in the network would be monitored and based on negative and positive points being given to nodes. These points will constitute in calculating the rank or the reputation factor of a node in the network. These factors have given some weight which is accounted to build up the trust value and trust rank, which is visible to all the nodes and can decide which node is more trustable and which is not. The lower ranking in the network means a malicious node and high rank would mean the genuine node. After ranking, we can find the node which may or may not misbehave in the future and try to prevent those nodes to cause serious security threats like Sybil attacks and Byzantine fault tolerance. These passive attacks are hard to discover and harder to prevent. Hence, this dynamic trust model will incorporate methods by which blockchain could be more secure and resilient. To get the application-based advantage of the following dynamic trust model, a supply chain model application would be used to record the peer-to-peer transactions for recording in the blockchain and further processing for trust ranking of the nodes. This application would generalize the use of all blockchain applications. Since the introduction of blockchain, everyone talks about the properties it offers—and they are actually quite unique. The introduction of blockchain was not made only to build application of Bitcoin, but to support the decentralized architecture and its work in the transaction processing. Therefore, blockchain also involves threats like any other new technology. Now, to remove those threats, as well as using blockchain widely, is the motivation for this project. Two of the threats which could be solved by devising a dynamic trust model are Sybil attacks and Byzantine fault tolerance. These passive attacks have disrupting impact on the whole network and are proven to be lethal for destroying architecture and applications running over it. The literature has wide discussion on security of blockchain, security, and trust of blockchain and its applications in different environments. Today’s supply chains have high standards for their requirements and even when the software works just fine, maybe it is not recent enough or it was not specified and built to satisfy these requirements. For instance, concurrent payment and transaction verifiability might be a huge issue nowadays in the supply chain finance, but maybe it was not rated as a high importance problem 12 years ago. Therefore, the software from 12 years ago complied with different requirements than the ones from today and was not built to handle that specific problem well. Requirements evolve, and so should the technology, in order to support them. The characteristics of blockchain architecture and dynamic trust models seem to be a good solution for many of the identified problems in supply chains to be reduced or neutralized. Figure 3.1 shows the general architecture of a blockchain with few blocks. More details of the blockchain can be found in the literature. These architectures are the perfect means to achieve traceability of a supply chain transaction, and so, they are useful to achieve provenance, as well. At the same time, they are a secure, incorruptible, and immutable way to store information, with a fast synchronization time, being perpetually available to anyone who has permission, anywhere within the network. It would also be the way to close the analog gaps, turning the chain fully digital, and leading to the possibility of a global overview.