半中心化的區塊鏈智能合約:以太坊區塊鏈上的中心化驗證及鏈下計算的智能合約

Semi-Centralized Blockchain Smart Contract : Smart Contract of Centralized verification and Off-Chain Execution on Ethereum Blockchain

林修平(Hsiu-Ping Lin)

指導教授 ： 廖世偉

國立臺灣大學/電機資訊學院/資訊工程學研究所/碩士(2017年)

https://doi.org/10.6342/NTU201704114

摘要

部署在區塊鏈上的智能合約強調的是它的去中心化優勢。但在區塊鏈下一波的革新技術尚未成熟落地前，隨著加密貨幣日漸走紅，區塊鏈上的虛擬貨幣價值迅速攀升，造成以該鏈貨幣為計算支付單位的區塊鏈技術如以太坊面臨開發和執行成本暴增。在這個情況下，我們提出一個半中心化的智能合約，將原本區塊鏈上去中心化的智能合約執行方式，搬至鏈下以中心化的方式來執行和驗證。目標是讓某些應用可以在不犧牲可驗證性及資料不可篡改性的前提下，藉由部分的取捨來提高執行效率和降低執行成本。我們並非提出一個新的共識演算法或是分片技術來提高區塊鏈的每秒交易量或每秒計算量。我們提出的是一個不同的合約執行方式，讓合約使用者可以在中心化、去中心化、執行效率和每秒計算量限制之間權衡，選擇自己合約適合的執行方式。

關鍵字

區塊鏈 ； 以太坊 ； Gcoin ； 去中心化 ； 智能合約 ； 鏈下計算

並列摘要

Smart contract deployed on Blockchain has the advantage of decentralization. However, with the increasing popularity and surging market cap of Blockchain tech- nology such as Ethereum, it has become much more expensive and difficult to deploy and execute a smart contract on Blockchain.
We propose a semi-centralized smart contract architecture to move the smart contract execution and verification away from the Ethereum blockchain. We hope applications can improve efficiency and save execution cost of their smart contract by balancing the trade-off between centralization and decentralization while retain computation verifiability and tamper-proof data.
We didn’t propose a new consensus algorithm or sharding scheme to increase transaction-per-second or compuation-per-second on Blockchain. What we proposed is a different approach to execute smart contract. User gets to decide between different property he desires such as centralization, decentralization, efficiency and computation-per-second and choose the best way to execute his smart contract.

並列關鍵字

Blockchain ； Ethereum ； Gcoin ； Decentralization ； Smart Contract ； Off-Chain Computation

參考文獻

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