物理不可複製函數(Physical Unclonable Function, 簡稱PUF)在硬體安全(Hardware Security)議題中，已經成為了一個非常有吸引力的解決方法。例如裝置的認證(Identification)與驗證(Authentication)以及加密學的密鑰生成(Cryptographic Key Generation)，皆可以使用物理不可複製函數的技術達成。
大多數的物理不可複製函數依賴電路結構中的特性來產生隨機的特徵。大至可分為兩類：基於延遲(Delay Based)的物理不可複製函數以及基於儲存元件(Storage Based)的物理不可複製函數。基於延遲的物理不可複製函數會有較多的額外面積需求(Area Overhead)，而大多基於儲存元件的物理不可複製函數則需要利用開機來初始化儲存元件，進而當作物理不可複製函數所需的特徵。
在本篇論文中，使用D型正反器(D Flip-Flop)來當作物理不可複製函數的基準。雖然本設計是基於儲存元件的物理不可複製函數，但我們卻不需要利用開機初始化，只要改變電路的信號及可達到物理不可複製函數所需要的特徵，並且也有非常好的可靠度(Reliability)、隨機性(Randomness)以及獨特性(Uniqueness)。

Physical Unclonable Function (PUF) is an attractive solution to the hardware security issues. PUFs can be used for the identification and authentication of devices and the cryptographic key generation.
Most PUFs rely on the variations of circuit element to generate random signature. The most popular PUFs include delay based PUFs and storage based PUFs. Delay based PUFs require more area overhead than storage based PUFs. The features of storage PUFs are normally generated by the initial values generated in the power up process.
In this thesis, we use D flip-flop as base of PUF element. The proposed design is storage based PUF, but this PUF does not have to power up for initializing. In stead, the PUF signature can be generated repeatedly through a control signal. Experimental results show that the proposed design achieves good reliability, randomness, and uniqueness.

致謝 i
摘要 ii
Abstract iii
目錄 iv
表目錄 v
圖目錄 vi
第一章 簡介 1
1.1. 研究動機與目標 1
1.2. 內容大綱 2
第二章 背景知識與相關研究 3
2.1. 物理不可複製函數 (Physical Unclonable Function) 3
2.1.1. 基於延遲的物理不可複製函數 (Delay Based PUF) 4
2.1.2. 基於儲存元件的物理不可複製函數 (Storage Based PUF) 6
2.2. 掃描鏈 (Scan Chain) 10
2.3. D型正反器 (D Flip-Flop) 11
2.4. 設定時間(Setup Time)與保持時間(Hold Time) 13
2.5. 同步化失敗(Synchronization Failure)與亞穩態(Metastability) 14
第三章 研究方法 16
3.1. 研究想法 16
3.2. 初步的實驗 17
第四章 實驗結果與分析 20
4.1. 物理不可複製函數的註冊(Enrollment)與雜訊(Noise Signal)加入 21
4.2. 可靠度(Reliability)的分析 23
4.3. 隨機性(Randomness)的分析 26
4.4. 獨特性(Uniqueness)的分析 26
第五章 結論 28
參考文獻 29

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