Distributed Ledger Technology (DLT) has emerged as a promising solution for constructing decentralized and trustworthy platforms in recent years. Although blockchain, as a form of distributed ledger technology known for its tamper resistance and trustworthiness, seems to be an ideal solution for addressing trust issues, common blockchain systems face limitations due to the ever-growing volume of data. In this paper, we propose a dynamic storage scheme calledEfficiency-awareLow-storageScalability (ELS), which allocates variable data storage for the distributed ledgers. Our approach is designed to provide load balancing and security, allowing dynamic nodes to join or exit the network seamlessly. We utilize graph theory to group storage nodes in the blockchain by determining their network distances. These groups are then mapped into points in a two-dimensional virtual plane, meaning that block storage depends on the coordinates within the virtual plane. To balance storage performance with the evolving block allocation strategy, we develop a Voronoi diagram-based method to achieve near real-time adoptions that meet dynamic allocation requirements in blockchain systems. Experimental evaluations have demonstrated that our approach can reduce storage requirements by approximately 93% at each node, compared to full replication in 10000 block chains.

Ensuring scalability in cryptocurrency systems is significant in guaranteeing real-world utility along with the remarkable increment of cryptographic currency. As an alternative in solving scalability issue, payment channel allows users to deliver extensive offline transactions without uploading massive transaction details to the blockchain, such that increasing efficiency can be achieved. However, the implementation of payment channel still encounters privacy concerns when considering the publicly available transaction amounts and the potentials in mining associations between transaction parties. In this paper, we propose a novel payment channel scheme, entitledCommitment-basedAnonymousPayment ChannEl (CAPE), to facilitate unlimited off-chain bidirectional payments while guaranteeing participants’ privacy. The proposed scheme adopts zero-knowledge proof (zk-SNARKs) and verifiable timed (VTD) commitments to ensure the anonymity of the relationship between on-chain and off-chain transactions, privacy of transaction amounts, and security of balances. We comprehensively formalize security definitions and present rigorous proofs for each security attribute. Experiment results further demonstrate the practical viability of CAPE.

Along with the development of the biological industry, the system of biological assets governance has a higher-level requirement in asset identity verification due to the demands of digitization and Financial Technology (FinTech). In order to achieve broad scalability and adaptability in the governance of biological assets' identities, this work proposes a Biological Assets Decentralized Identity Management (BA-DID) system that develops a Decentralized Identity (DID)-based solution to addressing the verification issues in biological assets while considering multi-dimensional requirements. Blockchain technology is the fundamental infrastructure of the system. Authenticated certificates of the asset owners verify identity attributes. Financial Service Institutions (FSI) and governance agencies act as issuers, providing Verifiable Credentials (VC) for biological assets by using a group of attributes over a consensus. The asset owners hold VCs and can be available to other organizations as proof of the corresponding asset attributes. Our evaluations have demonstrated that the proposed approach has superior performance in biological assets verification, security, and maintenance.