臺灣博碩士論文加值系統

台灣目前的期貨皆以國外大宗商品以及現金交割為主，而一般中小型生產者的農產品卻無法透過現有的期貨市場享有分散風險的好處。此外，現有的期貨交易資料皆儲存於期貨交易所，而期貨交易所的系統仍為傳統集中式的架構，因此一直都有系統崩潰、資料損毀等問題存在。
本研究期望透過建置一個實物期貨交易平台，幫助農牧業生產者與需求者直接媒合，減少中間商不當操作市場的問題。生產者能事先得知要生產的數量以及約定一個合理的價格，避免未來的不確定性。買方在訂單成立後若不需要商品也可將訂單以自訂的價格在平台上轉手，藉此分散買方的風險。
區塊鏈作為一個信任機器，擁有不可竄改以及避免單點故障的好處，因此我們將期貨合約及訂單的內容存於區塊鏈中來保證整體交易流程的安全。由於公鏈虛擬貨幣的價值較不穩定，我們採用法幣計算款項並引入銀行的角色確保金流的正確。金流都在系統外進行，但繳款資訊會包含於訂單內容中，並由銀行使用智能合約進行確認。
最後，我們比較了傳統的PoW與系統採用的PoA兩種共識機制。結果表明，PoA具有吞吐量優勢，可以為用戶帶來更好的體驗。

Futures in Taiwan are currently dominated by foreign bulk trading and cash delivery. However, small-sized agricultural producers cannot get the benefits of risk diversification through existing futures market. In addition, existing futures transaction data are stored in the futures exchange, and the system of futures exchange is still traditional centralized structures. Therefore, there have always been problems with system crashes, and data corruption.
This study expects to help agricultural producers and consumers directly match through the establishment of a physically delivered futures trading platform to reduce the problem of intermediaries' improper market operation. Producers can know the quantity to be produced in advance and agree on a reasonable price to avoid future price uncertainty. Buyers can resell the established order at a customized price if they need, thereby diversifying the risk.
As a trust machine, blockchain has the advantages of immutability and preventing a single point of failure. Therefore, we store the content of futures contracts and orders in blockchain to ensure transaction security. Since the value of cryptocurrency on the public chain is unstable, we still use fiat currency for the payment and introduce the role of bank to ensure the correctness of the cash flow. The cash flow is performed outside the system, but payment information is included in the order content and confirmed by the bank using smart contract.
Finally, we compared the PoW consensus algorithm with the PoA adopted by the system. The result shows that PoA has the advantage in throughput and can give users better experience.

摘要 ............................................................................................................. i
Abstract ......................................................................................................... ii
誌謝 ........................................................................................................... iii
Table of Contents ......................................................................................... iv
List of Tables ................................................................................................ vi
List of Figures ............................................................................................. vii
1 Introduction ............................................................................................. 1
1.1 Motivation ............................................................................................................ 1
1.2 Objective .............................................................................................................. 2
1.3 Outline .................................................................................................................. 3
2 Background and Related Work ............................................................... 4
2.1 Blockchain ............................................................................................................ 4
2.1.1 Overview ......................................................................................................... 4
2.1.2 Ethereum .......................................................................................................... 5
2.1.3 Smart Contract ................................................................................................. 7
2.2 Related Work ........................................................................................................ 8
3 System Design ....................................................................................... 10
3.1 Application Scenario .......................................................................................... 10
3.1.1 Overview ....................................................................................................... 10
3.1.2 Stage 1 ........................................................................................................... 11
3.1.3 Stage 2 ........................................................................................................... 13
3.1.4 Stage 3 ........................................................................................................... 15
3.2 Architecture Design ............................................................................................ 17
3.2.1 Overview ....................................................................................................... 17
3.2.2 Consortium Chain .......................................................................................... 18
3.2.3 Backend ......................................................................................................... 19
3.2.3.1 User API 21
3.2.3.2 Contract API 22
3.2.3.3 Order API 23
3.2.4 Frontend ......................................................................................................... 24
3.3 Smart Contract Design ....................................................................................... 25
3.3.1 User Manager ................................................................................................ 25
3.3.2 Contract Manager .......................................................................................... 26
3.3.3 Order Manager ............................................................................................... 27
4 System Demonstration ........................................................................... 30
4.1 Platform Sign Up ................................................................................................ 30
v
4.2 Contract Display ................................................................................................. 31
4.3 New Contract ...................................................................................................... 32
4.4 Buy contract ....................................................................................................... 33
4.5 Confirm Order .................................................................................................... 33
4.6 Pay Deposit......................................................................................................... 35
4.7 Resell Order ........................................................................................................ 35
4.8 Buy Resale Order ............................................................................................... 37
4.9 Confirm Resale Order and Pay Deposit ............................................................. 38
4.10 Expired Order ................................................................................................... 39
4.11 Pay Balance ...................................................................................................... 40
5 System Analysis ..................................................................................... 41
5.1 Test Environment ............................................................................................... 41
5.2 Gas Consumption ............................................................................................... 41
5.3 Function Throughput .......................................................................................... 42
5.4 Consensus Algorithm and Throughput............................................................... 43
6 Conclusion and Future Work ................................................................. 45
6.1 Conclusion .......................................................................................................... 45
6.2 Future Work ....................................................................................................... 46
7 Reference ............................................................................................... 47

Journals
[7] G. Wood, "Ethereum: a secure decentralised generalised transaction ledger," Ethereum Project Yellow Paper, vol. 151, pp. 1-32, 2014.
[11] X. Liu, K. Muhammad, J. Lloret, Y.-W. Chen, and S.-M. Yuan, "Elastic and cost-effective data carrier architecture for smart contract in blockchain," Future Generation Computer Systems, vol. 100, pp. 590-599, 2019.
[15] V. Gatteschi, F. Lamberti, C. Demartini, C. Pranteda, and V. Santamaría, "Blockchain and smart contracts for insurance: Is the technology mature enough?," Future Internet, vol. 10, no. 2, p. 20, 2018.
[16] P. Treleaven, R. G. Brown, and D. Yang, "Blockchain technology in finance," Computer, vol. 50, no. 9, pp. 14-17, 2017.
[18] W.-T. Tsai et al., "Blockchain systems for trade clearing," The Journal of Risk Finance, 2020.
[24] M. Avital, R. Beck, J. King, M. Rossi, and R. Teigland, "Jumping on the Blockchain Bandwagon: Lessons of the Past and Outlook to the Future," 2016.
Conference Preoceedings
[2] H. Subramanian, "Decentralized blockchain-based electronic marketplaces," Communications of the ACM, vol. 61, no. 1, pp. 78-84, 2017.
[5] D. Mingxiao, M. Xiaofeng, Z. Zhe, W. Xiangwei, and C. Qijun, "A review on consensus algorithm of blockchain," in 2017 IEEE International Conference on Systems, Man, and Cybernetics (SMC), 2017: IEEE, pp. 2567-2572.
[6] Y. Yuan and F.-Y. Wang, "Towards blockchain-based intelligent transportation systems," in 2016 IEEE 19th International Conference on Intelligent Transportation Systems (ITSC), 2016: IEEE, pp. 2663-2668.
[8] M. Alharby, A. Aldweesh, and A. van Moorsel, "Blockchain-based smart contracts: A systematic mapping study of academic research (2018)," in Proceedings of the 2018 International Conference on Cloud Computing, Big Data and Blockchain, 2018.
[10] S. Kalra, S. Goel, M. Dhawan, and S. Sharma, "ZEUS: Analyzing Safety of Smart Contracts," in NDSS, 2018, pp. 1-12.
[13] A. Azaria, A. Ekblaw, T. Vieira, and A. Lippman, "Medrec: Using blockchain for medical data access and permission management," in 2016 2nd International Conference on Open and Big Data (OBD), 2016: IEEE, pp. 25-30.
[17] T. Wu and X. Liang, "Exploration and practice of inter-bank application based on
48
blockchain," in 2017 12th International Conference on Computer Science and Education (ICCSE), 2017: IEEE, pp. 219-224.
[20] D. Duffie, N. Gârleanu, and L. H. Pedersen, "Over‐the‐counter markets," Econometrica, vol. 73, no. 6, pp. 1815-1847, 2005.
[21] Y. Coşkun, "The limitations of transparency policy in OTC markets and derivatives trading," Journal of Securities Operations & Custody, vol. 4, no. 2, pp. 122-133, 2011.
[22] R. Beck, J. Stenum Czepluch, N. Lollike, and S. Malone, "Blockchain–the gateway to trust-free cryptographic transactions," 2016.
[25] V. P. Ranganthan, R. Dantu, A. Paul, P. Mears, and K. Morozov, "A Decentralized Marketplace Application on the Ethereum Blockchain," in 2018 IEEE 4th International Conference on Collaboration and Internet Computing (CIC), 2018: IEEE, pp. 90-97.
[26] C.-H. Liao, Y.-W. Teng, and S.-M. Yuan, "Blockchain-Based Cross-Organizational Integrated Platform for Issuing and Redeeming Reward Points," in 2019 Tenth International Symposium on Information and Communication Technology (SoICT), 2019: ACM, pp. 407–411.
[41] E. Palm, O. Schelén, U. Bodin, and R. Hedman, "The Exchange Network: An Architecture for the Negotiation of Non-Repudiable Token Exchanges," in IEEE International Conference on Industrial Informatics (INDIN), Helsinki, Finland, 23-25 June 2019, 2019: IEEE.
Theses
[3] Y.-L. Lin, "Master Thesis: A Study on the Application of Blockchain Technology in Taiwan's Securities and Futures Markets," Master, 2017.
Web Pages
[1] "何謂期貨交易何謂期貨交易." TAIWAN FUTURES EXCHANGE. https://www.taifex.com.tw/cht/9/futuresQA#q1 (accessed JAN 29, 2020).
[9] "Solidity." Ethereum. https://solidity.readthedocs.io/en/v0.6.8/ (accessed MAY 21, 2020).
[12] "Ethereum 2.0 Specification." Ethereum. https://github.com/ethereum/eth2.0-specs (accessed MAY 21, 2020).
[14] "OpenBazaar Features." OpenBazaar. https://openbazaar.org/features/ (accessed MAY 26, 2020).
[19] "Nasdaq Linq Enables First-Ever Private Securities Issuance Documented With Blockchain Technology." Nasdaq. https://www.nasdaq.com/about/press-center/nasdaq-linq-enables-first-ever-private-securities-issuance-documented-blockchain (accessed JUN 1, 2020).
[23] C. B. MURPHY. "Over-The-Counter – OTC."
49
https://www.investopedia.com/terms/o/otc.asp (accessed APR 10, 2020).
[27] "MetaMask Docs." MetaMask. https://metamask.github.io/metamask-docs/ (accessed APR 18, 2020).
[28] D. Miller. "Bootstrap Registration Page with Floating Labels." Start Bootstrap. https://startbootstrap.com/snippets/registration-page/ (accessed FEB 12, 2020).
[29] StockSnap. "Bananas." Pixabay. https://cdn.pixabay.com/photo/2015/03/30/12/43/bananas-698608_960_720.jpg (accessed JUL 28, 2020).
[30] C. Jeria. "Metamask Logo." Metamask. https://github.com/MetaMask/brand-resources (accessed JUL 28, 2020).
[31] D. Miller. "Shop Homepage." Start Bootstrap. https://startbootstrap.com/templates/shop-homepage/ (accessed FEB 12, 2020).
[32] P. D. "Strawberry." Pixabay. https://cdn.pixabay.com/photo/2017/05/07/19/32/strawberry-2293337_960_720.jpg (accessed JUL 28, 2020).
[33] Alicja. "Bananas." Pixabay. https://cdn.pixabay.com/photo/2018/09/24/20/12/bananas-3700718_960_720.jpg (accessed JUL 28, 2020).
[34] PublicDomainPictures. "Pork." Pixabay. https://cdn.pixabay.com/photo/2012/12/11/21/28/pork-69429_960_720.jpg (accessed JUL 28, 2020).
[35] Couleur. "Strawberries." Pixabay. https://cdn.pixabay.com/photo/2016/04/24/19/41/strawberries-1350482_960_720.jpg (accessed JUL 28, 2020).
[36] D. Miller. "Shop Item." Start Bootstrap. https://startbootstrap.com/templates/shop-item/ (accessed FEB 12, 2020).
[37] S. P. Bhatt. "Checkout." Orbit Themes. https://github.com/orbitthemes/checkout (accessed FEB 13, 2020).
[38] Daria. "Peach." Pixabay. https://cdn.pixabay.com/photo/2018/05/24/02/07/peach-3425656_960_720.jpg (accessed JUL 28, 2020).
[39] "Apache JMeter." Apache Software Foundation. https://jmeter.apache.org/index.html (accessed MAY 15, 2020).
[40] "期貨交易系統期貨交易系統." TAIWAN FUTURES EXCHANGE. https://www.taifex.com.tw/cht/1/historyOfSystem (accessed MAY 24, 2020).
Online Database
[4] S. Nakamoto. Bitcoin: A peer-to-peer electronic cash system [Online] Available: http://www.bitcoin.org/bitcoin.pdf