Blockchain is widely used in encrypted currency, Internet of Things (IoT), supply chain finance, data sharing, and other fields. However, there are security problems in blockchains to varying degrees. As an important component of blockchain, hash function has relatively low computational efficiency. Therefore, this paper proposes a new scheme to optimize the blockchain hashing algorithm based on PRCA (Proactive Reconfigurable Computing Architecture). In order to improve the calculation performance of hashing function, the paper realizes the pipeline hashing algorithm and optimizes the efficiency of communication facilities and network data transmission by combining blockchains with mimic computers. Meanwhile, to ensure the security of data information, this paper chooses lightweight hashing algorithm to do multiple hashing and transforms the hash algorithm structure as well. The experimental results show that the scheme given in the paper not only improves the security of blockchains but also improves the efficiency of data processing.

Existing blockchains, especially public blockchains, face the challenges of scalability which means the processing capacity will not get better with the addition of nodes, making it somewhat infeasible for mobile computing applications. Some improved technologies are known to speed up processing capacity by shrinking the consensus group, increasing the block capacity and/or shortening the block interval. Even these solutions are met with major problems such as storage limitations and weak security. To face the realistic application scenarios for blockchain technology in the mobile realm, we propose a new public blockchain designed based on sharding, aggregate signature and cryptographic sortition which we call SAC. In SAC, the transaction rate increases with the number of shards while the length of the consensus signature is a constant. Meanwhile, in SAC, the assignment of consensus representatives is controlled by a verifiable random function, which can effectively solve the problem of centralized consensus. In addition, this paper analyzes the performance of SAC to give adequate comparison with other sharding technologies while also giving a rational security analysis. Our experimental results clearly show the potential applicability of this novel blockchain protocol to in mobile computation.

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With the vigorous development of blockchain technology represented by bitcoin, blockchain technology has gradually entered the stage of blockchain 3.0 characterized by “programmable society”. And the application of blockchain technology in all walks of life has achieved actual results. Blockchain technology has typical characteristics of decentralization, Tamper-resistant data, information openness and transparency, and natural fit with the application requirements in the field of certificate tracing, which makes the development of the applications of blockchain deposit and traceability in full swing. First, this paper describes the concept, application process, key technology of blockchain deposit and traceability, the three application architectures of blockchain deposit and traceability, and the overall architecture of its system. Then, it introduces the application of scenarios and the blockchain deposit and traceability in various fields. Next, it discusses the issues existing in the development of the application of blockchain deposit and traceability. Finally, the paper also expresses the best wishes for the future of its application.

As one of the most widely used federated chains, hyperledger fabric uses many cryptographic algorithms to ensure the security of information on the chain, but the ECDSA cryptographic algorithm used in the fabric system has backdoor security risks. In this paper, the authors adopt SM2 algorithm to replace the corresponding ECDSA algorithm for blockchain design based on fabric platform. Firstly, they optimize the part of SM2 signature algorithm process with inverse operation and effectively reduce the time complexity by reducing the inverse operation in the whole process, and the experimental results show that the improved SM2 algorithm improves the signature and verification efficiency by about 5.7%. Secondly, by adding SM2 algorithm template and interface to the BCCSP module of fabric platform to realize the shift value of SM2 algorithm and compare the performance with the native fabric system, the network startup time is reduced by about 29%. The experimental results show the effectiveness of the improved SM2 algorithm, and also the performance of the optimized fabric system is improved.