物聯網（IoT）的蓬勃發展為人們的生活提供各種便利的服務，卻也成為有心人士進行網路攻擊的媒介，因此確保物聯網設備身份真實性的安全議題開始備受重視。
由於物聯網設備在生活中無處不在，給了攻擊者許多利用物理攻擊(physical attack)和克隆攻擊(cloning attack)來獲取設備身份認證訊息的機會，進而偽造成合法設備的身份。此外，現有的物聯網設備身份認證系統大多是依靠單一機構的集中式架構，可能存在單點故障問題或信任問題疑慮。
為了解決上述問題，本文提出基於物理不可克隆功能(PUF)的區塊鏈(blockchain)身份認證方案，利用設備晶片的PUF產生認證資訊以避免因為物理攻擊和克隆攻擊所造成的身份偽造問題，並使用區塊鏈技術結合零知識證明協議來實現身份認證流程，即使在公開透明的網路依然能夠確保認證的安全性。認證流程完成後，認證結果將會被紀錄到鏈上避免遭到竄改，並利用聚合簽章技術以避免設備收到的資訊遭到中間人攻擊。安全與性能分析表明我們提出的方法對於物聯網相關的安全議題皆有較好的抵禦能力，並且符合物聯網設備計算資源受限的需求。

The vigorous development of the Internet of Things (IoT) provides a variety of convenient services for people, but it has also become a hot target for hackers to carry out malicious attacks. Therefore, the security issue of ensuring the authenticity of the identity of the IoT devices has begun to attract attention.
As IoT devices are ubiquitous in life, it provides attackers with many opportunities to use physical attacks and cloning attacks to obtain device authentication information, thereby forging the identity of legitimate devices. Besides, most of the existing identity authentication systems for IoT devices rely on the centralized architecture of a single organization, and there may be a single point of failure or trust issues.
To solve the above problems, this paper proposes a physical unclonable function (PUF) based identity authentication scheme with blockchain, which uses the PUF of the device chip to generate authentication information to avoid identity forgery caused by physical attacks and cloning attacks. And the use of blockchain technology combined with the zero-knowledge proof protocol to realize the identity authentication process can still ensure the security of authentication even in an open and transparent network. After the authentication process is completed, the authentication result will be recorded on the chain to avoid tampering, and the aggregate signature technology will be used to avoid man-in-the-middle attacks on the information received by the device. Security and performance analysis shows that the method we proposed has good resistance to the security issues of the IoT, and can meet the needs of the IoT devices for limited computing resources.

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