目前区块链的容量受到网络里存储空间最小的节点的限制,提出了区块链存储容量可扩展模型,该模型将一条完整的区块链副本进行分片处理,并将分片数据保存在一定比例的节点中。同时,模型增加了验证节点,对存储数据的节点进行基于数据可检...目前区块链的容量受到网络里存储空间最小的节点的限制,提出了区块链存储容量可扩展模型,该模型将一条完整的区块链副本进行分片处理,并将分片数据保存在一定比例的节点中。同时,模型增加了验证节点,对存储数据的节点进行基于数据可检索性证明(proofs of retrievability,POR)方法的实时检测,并记录更新存储节点稳定性值,依此选择高稳定性节点来储存新产生的数据副本,提高了数据存储的稳定性。最后,模型在多节点中正常运行、节点故障和有恶意攻击时的实验表明,区块链存储容量可扩展模型在具有稳定性、容错性和安全性的同时,有效地增加了区块链的存储扩展性。展开更多
There is a great thrust in industry toward the development of more feasible and viable tools for storing fast-growing volume, velocity, and diversity of data, termed ＇big data＇. The structural shift of the storage m...There is a great thrust in industry toward the development of more feasible and viable tools for storing fast-growing volume, velocity, and diversity of data, termed ＇big data＇. The structural shift of the storage mechanism from traditional data management systems to NoSQL technology is due to the intention of fulfilling big data storage requirements. However, the available big data storage technologies are inefficient to provide consistent, scalable, and available solutions for continuously growing heterogeneous data. Storage is the preliminary process of big data analytics for real-world applications such as scientific experiments, healthcare, social networks, and e-business. So far, Amazon, Google, and Apache are some of the industry standards in providing big data storage solutions, yet the literature does not report an in-depth survey of storage technologies available for big data, investigating the performance and magnitude gains of these technologies. The primary objective of this paper is to conduct a comprehensive investigation of state-of-the-art storage technologies available for big data. A well-defined taxonomy of big data storage technologies is presented to assist data analysts and researchers in understanding and selecting a storage mecha- nism that better fits their needs. To evaluate the performance of different storage architectures, we compare and analyze the ex- isling approaches using Brewer＇s CAP theorem. The significance and applications of storage technologies and support to other categories are discussed. Several future research challenges are highlighted with the intention to expedite the deployment of a reliable and scalable storage system.展开更多
云存储中的数据可能会遭受非法窃取或篡改,从而使用户数据的机密性面临威胁。为了更加安全、高效地存储海量数据,提出一种支持索引、可追溯、可验证的云存储与区块链结合的存储模型CBaaS(Cloud and Blockchain as a service),它可以增...云存储中的数据可能会遭受非法窃取或篡改,从而使用户数据的机密性面临威胁。为了更加安全、高效地存储海量数据,提出一种支持索引、可追溯、可验证的云存储与区块链结合的存储模型CBaaS(Cloud and Blockchain as a service),它可以增强云中数据的可信性。另外,区块链的协商一致协议导致交易的吞吐量低,处理速度慢,严重制约了去中心化应用的发展。基于此,文中实现了一个三层架构的区块链模型TBchain(Three-tier architecture Blockchain),其通过分割区块链的一部分并将其锁定在更高级别区块链的块中提高区块链的可伸缩性,从而提高区块链中交易的吞吐量。此外,区块链由于去中心化的需求占用了海量节点的大量存储空间,这极大地限制了以区块链技术为基础的数据库系统的发展与应用。通过TBchain将一部分交易存储在本地,增加了区块链存储容量的可扩展性。云存储对象元数据中的ETag标示一个Object的内容,可以用来检查Object内容是否发生变化。将云存储中的对象元数据存储在区块链上,利用ETag值可以用于检查Object内容是否发生变化的特性和区块链上的数据不可篡改的特性来验证云上存储的数据是否安全,从而提高云上存储数据的可信性。实验结果表明,TBchain模型提高了区块链的可伸缩性和区块链存储容量的可扩展性,CBaaS模型也有效地提高了云上存储数据的可信性。展开更多
With the development of satellite miniaturization and remote sensing,the establishment of microsatellite constellations is an inevitable trend.Due to their limited size,weight,and power,spaceborne storage systems with...With the development of satellite miniaturization and remote sensing,the establishment of microsatellite constellations is an inevitable trend.Due to their limited size,weight,and power,spaceborne storage systems with excellent scalability,performance,and reliability are still one of the technical bottlenecks of remote sensing microsatellites.Based on the commercial off-the-shelf field-programmable gate array and memory devices,a spaceborne advanced storage system(SASS)is proposed in this paper.This work provides a dynamic programming,queue scheduling multiple-input multiple-output cache technique and a high-speed,high-reliability NAND flash controller for multiple microsatellite payload data.Experimental results show that SASS has outstanding scalability with a maximum write rate of 2429 Mb/s and preserves at least 78.53%of the performance when a single NAND flash fails.The scheduling technique effectively shortens the data scheduling time,and the data remapping method of the NAND flash controller can reduce the retention error by at least 50.73%and the program disturbance error by at least 37.80%.展开更多
针对现有存储算法无法兼顾文件定制化可靠性保证和系统良好可扩展性这一问题,提出一种全分布式的支持容错QoS(Quality of Service)的文件存储算法。算法允许文件被存储副本数量与其可靠性需求相匹配,无单一故障点与瓶颈点。此外,实验结...针对现有存储算法无法兼顾文件定制化可靠性保证和系统良好可扩展性这一问题,提出一种全分布式的支持容错QoS(Quality of Service)的文件存储算法。算法允许文件被存储副本数量与其可靠性需求相匹配,无单一故障点与瓶颈点。此外,实验结果表明算法可保持节点间负载均衡,实现系统资源的高效利用。展开更多
文摘目前区块链的容量受到网络里存储空间最小的节点的限制,提出了区块链存储容量可扩展模型,该模型将一条完整的区块链副本进行分片处理,并将分片数据保存在一定比例的节点中。同时,模型增加了验证节点,对存储数据的节点进行基于数据可检索性证明(proofs of retrievability,POR)方法的实时检测,并记录更新存储节点稳定性值,依此选择高稳定性节点来储存新产生的数据副本,提高了数据存储的稳定性。最后,模型在多节点中正常运行、节点故障和有恶意攻击时的实验表明,区块链存储容量可扩展模型在具有稳定性、容错性和安全性的同时,有效地增加了区块链的存储扩展性。
文摘There is a great thrust in industry toward the development of more feasible and viable tools for storing fast-growing volume, velocity, and diversity of data, termed ＇big data＇. The structural shift of the storage mechanism from traditional data management systems to NoSQL technology is due to the intention of fulfilling big data storage requirements. However, the available big data storage technologies are inefficient to provide consistent, scalable, and available solutions for continuously growing heterogeneous data. Storage is the preliminary process of big data analytics for real-world applications such as scientific experiments, healthcare, social networks, and e-business. So far, Amazon, Google, and Apache are some of the industry standards in providing big data storage solutions, yet the literature does not report an in-depth survey of storage technologies available for big data, investigating the performance and magnitude gains of these technologies. The primary objective of this paper is to conduct a comprehensive investigation of state-of-the-art storage technologies available for big data. A well-defined taxonomy of big data storage technologies is presented to assist data analysts and researchers in understanding and selecting a storage mecha- nism that better fits their needs. To evaluate the performance of different storage architectures, we compare and analyze the ex- isling approaches using Brewer＇s CAP theorem. The significance and applications of storage technologies and support to other categories are discussed. Several future research challenges are highlighted with the intention to expedite the deployment of a reliable and scalable storage system.
文摘云存储中的数据可能会遭受非法窃取或篡改,从而使用户数据的机密性面临威胁。为了更加安全、高效地存储海量数据,提出一种支持索引、可追溯、可验证的云存储与区块链结合的存储模型CBaaS(Cloud and Blockchain as a service),它可以增强云中数据的可信性。另外,区块链的协商一致协议导致交易的吞吐量低,处理速度慢,严重制约了去中心化应用的发展。基于此,文中实现了一个三层架构的区块链模型TBchain(Three-tier architecture Blockchain),其通过分割区块链的一部分并将其锁定在更高级别区块链的块中提高区块链的可伸缩性,从而提高区块链中交易的吞吐量。此外,区块链由于去中心化的需求占用了海量节点的大量存储空间,这极大地限制了以区块链技术为基础的数据库系统的发展与应用。通过TBchain将一部分交易存储在本地,增加了区块链存储容量的可扩展性。云存储对象元数据中的ETag标示一个Object的内容,可以用来检查Object内容是否发生变化。将云存储中的对象元数据存储在区块链上,利用ETag值可以用于检查Object内容是否发生变化的特性和区块链上的数据不可篡改的特性来验证云上存储的数据是否安全,从而提高云上存储数据的可信性。实验结果表明,TBchain模型提高了区块链的可伸缩性和区块链存储容量的可扩展性,CBaaS模型也有效地提高了云上存储数据的可信性。
基金supported by the Fundamental Research Funds for the Zhejiang Provincial Universities,China(No.2021XZZX038)。
文摘With the development of satellite miniaturization and remote sensing,the establishment of microsatellite constellations is an inevitable trend.Due to their limited size,weight,and power,spaceborne storage systems with excellent scalability,performance,and reliability are still one of the technical bottlenecks of remote sensing microsatellites.Based on the commercial off-the-shelf field-programmable gate array and memory devices,a spaceborne advanced storage system(SASS)is proposed in this paper.This work provides a dynamic programming,queue scheduling multiple-input multiple-output cache technique and a high-speed,high-reliability NAND flash controller for multiple microsatellite payload data.Experimental results show that SASS has outstanding scalability with a maximum write rate of 2429 Mb/s and preserves at least 78.53%of the performance when a single NAND flash fails.The scheduling technique effectively shortens the data scheduling time,and the data remapping method of the NAND flash controller can reduce the retention error by at least 50.73%and the program disturbance error by at least 37.80%.
文摘针对现有存储算法无法兼顾文件定制化可靠性保证和系统良好可扩展性这一问题,提出一种全分布式的支持容错QoS(Quality of Service)的文件存储算法。算法允许文件被存储副本数量与其可靠性需求相匹配,无单一故障点与瓶颈点。此外,实验结果表明算法可保持节点间负载均衡,实现系统资源的高效利用。
