共識協議（Consensus Protocol）是區塊鏈（Blockchain）的核心，它決定了區塊鏈的運作方式。而去中心化（Decentralization）是區塊鏈能發展至今的重要因素之一，也是區塊鏈最顯著的特徵之一。隨著智能家居（Smart Home）時代的到來，區塊鏈隨著物聯網 (Internet of Things) 已經開始進入我們的生活。但是，現今各類不同的共識算法的基礎依然為算力、持幣數量等等，而各種不同的智能設備之間的差距越來越顯著，這樣的作法顯然並不太適用於智能家居環境中，而且容易造成整個系統難以達到真正的去中心化。因此，本論文將在工作量證明（Proof of Work）的基礎上提出一個新的共識演算法，其透過改變工作量證明中區塊產生時要求的前 X 位驗證值，並且降低計算難度，以免造成大量延遲。同時，在上鏈時不再比較廣播的速度，而是通過比較一定時間內產生區塊的隨機數（Nonce) 大小來決定出塊的節點 (Node)。這樣做雖然犧牲了一定的出塊時間，但是去中心化程度可以大大提高。最後，實驗結果顯示：此協議在去中心化程度上的表現比較同類演算法有顯著的改善。

The consensus protocol is the core of the blockchain and it determines how the blockchain works. The decentralization is one of the important factors that the blockchain can be developed so far and it is also one of the most significant features of the blockchain. With the advent of the smart home era, the blockchain has begun to enter our lives along with the Internet of things. However, the basis of various consensus algorithms is still computing power, number of coins, etc, and the gap between different smart devices is becoming more and more significant. Such an approach is obviously not suitable for the smart home environment. Obviously, it is easy to cause the entire system to be difficult to achieve the true decentralization. Therefore, this thesis will propose a new consensus protocol based on the proof of work (PoW) by changing the first X-bit verification value required when the block is generated in PoW and reducing the difficulty of calculation to avoid causing a lot of delay. At the same time, the broadcast speed is no longer compared when linking to the chain. Instead, the node to generate the block is determined by comparing the random number (nonce) generated in a certain period. Undoubtedly, this sacrifices a certain amount of the block time but the degree of decentralization can be greatly improved. Finally, the experimental results succssfully show that the performance of our proposed protocol significantly outperforms the closely related algorithms.

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