# Centralized vs. Decentralized: Performance Comparison between BigchainDB and Amazon QLDB
## 2 Literature Review
For example, paper [7] focuses on the uses of ledger databases as a traditional database manager. The authors review the Centralized Ledger Databases (CLD)-based centralized ledger technology and the permissioned blockchain technology-based decentralized ledger technology. They examine LedgerDB as a centralized ledger database and Hyperledger Fabric, FalconDB, BlockchainDB, ChainifyDB, BigchainDB, and Blockchain \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Database** & **2014** & **2015** & **2016** & **2017** & **2018** & **2019** & **2020** & **2021** & **2022** \\ \hline Web of Science & 1 & 0 & 2 & 5 & 19 & 34 & 23 & 29 & 25 \\ \hline IEEE Xplore & 1 & 0 & 2 & 3 & 12 & 30 & 18 & 13 & 12 \\ \hline Scopus & 1 & 0 & 1 & 6 & 28 & 51 & 55 & 60 & 44 \\ \hline Science Direct & 0 & 4 & 0 & 1 & 17 & 29 & 60 & 101 & 122 \\ \hline Wiley & 1 & 0 & 2 & 3 & 8 & 23 & 19 & 23 & 25 \\ \hline \hline \end{tabular}
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Table 4: Each database’s annual number of papers with “decentralized/decentralized ledgers” keywords. Figure 2: (a) Evolutionary trend in the number of publications covering centralized ledgers; (b) Evolutionary trend in the number of publications covering decentralized ledgers. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Database** & **2014** & **2015** & **2016** & **2017** & **2018** & **2019** & **2020** & **2021** & **2022** \\ \hline Web of Science & 0 & 0 & 0 & 0 & 1 & 3 & 2 & 5 & 0 \\ \hline IEEE Xplore & 0 & 0 & 0 & 0 & 0 & 4 & 0 & 0 & 3 \\ \hline Scopus & 0 & 0 & 0 & 0 & 3 & 5 & 4 & 4 & 4 \\ \hline Science Direct & 0 & 2 & 0 & 0 & 4 & 8 & 8 & 10 & 16 \\ \hline Wiley & 0 & 0 & 0 & 2 & 4 & 3 & 7 & 5 & 5 \\ \hline \hline \end{tabular}
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Table 3: Each database’s annual number of papers with “centralized/centralized ledgers” keywords. Relational Database as permissioned blockchain-based databases. In their paper, the authors discuss the strengths and weaknesses of the reviewed technologies and present a comparison of them. Some researchers and practitioners have concentrated their research on applications based on centralized and/or decentralized ledger technologies. Thus, the research presented in [8] focuses on the role of centralized and decentralized ledgers in the money supply process. The authors conduct a SWOT analysis to identify the strengths, weaknesses, opportunities and threats of using both systems in finance. The authors reveal that in several aspects, \"the strengths and opportunities of decentralized ledgers outweigh those of centralized ledgers\". However, \"while decentralized ledgers are expected to disrupt finance and introduce unprecedented opportunities, centralized ledgers ensure the continuity of the current financial systems\" [8]. Over time, the decentralized ledger technique, blockchain [9], has been used to implement numerous decentralized systems; for example, in payment systems, supply chain management, tracking and tracing, etc. Thus, various studies have demonstrated that the use of blockchain-based applications in supply chain networks can enhance product tracking and enable full product traceability [10; 11; 12; 13]. Recently, blockchain has attracted attention to realize secure and robust data management systems for the Internet of Things (IoT) and Industrial Internet of Things (IIoT) [14]. Paper [15] demonstrates the use of a decentralized and immutable ledger, such as blockchain, as a common platform for companies in the logistics industry, along with the use of IoT sensor devices for tracking. Thus, the authors present a blockchain smart contract system that integrates the Internet of Things (IoT) technology to ensure product management in a logistics system, with a significant impact in improving security, speed, trust, and transparency for the data exchange that takes place in supply chains. In [16], the author evaluates the potential of blockchain technology in driving future IoT development towards the Ledger of Things.