在當今的區塊鏈（Blockchain）系統中，要設計與中心化支付系統（Centralized Payment System）具相同安全且高吞吐量（Throughput）將是一大挑戰，而其中一種解決方案（Solution）就是使用分片（Sharding ）技術。而本論文的目標則是針對分片技術做改進，以提升吞吐量及具備可延展性（Scalability）。其將透過引入分片控制器（Shard Controller）來管理（Manage）、接收（Accept）與終止（Abort）交易（Transaction），以有效減少分片之間相互傳遞訊息的額外費用（Overhead），進而減少延遲（Latency），並且達到吞吐量的提升。最後，透過亞馬遜網頁服務（Amazon Web Service, AWS）彈性雲端運算（Elastic Compute Cloud, EC2）平台進行評估（Evaluation）和測試（Test）；結果顯示，本論文所提機制較文獻上相近機制在吞吐量與延遲方面均有顯著改善。

In today's blockchain system, it is a big challenge to have the same security level and high throughput as the centralized payment system. One of the solutions to achieve this goal is to use the technology of sharding. Therefore, the goal of this thesis lies in improving throughput and achieving scalability for the blockchain system with sharding. By introducing a shard controller to manage, accept, and abort transaction messages to the blockchain system with sharding to effectively reduce the overhead of transferring messages between shards, latency is then reduced, increasing throughput accordingly. Finally, evaluation and test are arranged on the elastic compute cloud (EC2) platform of the Amazon web service (AWS). Our results show that our proposed mechanism outperforms the related mechanism in the literature in terms of throughput and latency.

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