本研究針對過去的最短路徑在圖形隱匿問題，提出一套提高最短路徑隱私 保護程度的方法。過去研究中，已有許多針對最短路徑在圖形中所暴露出的問 題提出解決的方法，在這些解決的方法中，大致可分成兩種，其中一種方式是 擾動圖形中的權重，使得攻擊者無法辨識最短路徑上原始的權重值，但仍可維 持最短路徑的途徑：另一種方式是擾動圖形中的權重，使得圖形中相同的起點 終點對包含二條以上的最短路徑，讓攻擊者無法準確的辨識真正的最短路徑為 何。但過去的研究中，仍未考慮到當攻擊者擁有節點分支度數的背景知識時，
攻擊者仍有可能利用最短路徑上的節點分支度，來辨識真實的最短路徑，因 此，本研究提出一個處理上述問題的概念 - (k1, k2)-shortest path privacy。(k1, k2)-shortest path privacy 不僅能夠讓圖形中，同一對起點-終點對包含 k1條最短 路徑，並且在這 k1條最短路徑上的任一一個非重疊節點必定能夠找到其他 k2 - 1 個節點與其有相同的分支度數，故能夠防止攻擊者利用分支度數的攻擊方法來 辨識出真正的最短路徑。
本研究提出三種節點分群方法與兩種加邊方法來達成(k1, k2)-shortest path
privacy，並試圖找出一種節點-加邊的方法配對能夠以最低的隱匿成本以及圖形 破壞程度最低的方式建立(k1, k2)隱匿圖。此三種節點分群方法分別為 Modified k-means、Sorting、Dynamic Programming；兩種加邊方法分別為：Random、
Transfer Node First。
在實驗結果與分析的部分，我們利用四種評估指標來衡量各方法配對所產 生的圖形。此四種指標分別為：執行時間、加邊數量、平均群聚係數、平均最 短路徑長度。由此四個指標來衡量圖形的圖形建立時間、建立隱匿圖所需的新 連結數量、隱匿圖的圖形結構與原始圖形的差異。在實驗結果最後中，我們針 對各種方法組合在上述各項指標給予分析與排序以提供參考。
本研究中隱私保護的對象只考慮一對起點-終點對的最短路徑，目前並未考
慮多對最短路徑的分支度隱私保護，其原因是若要做多對的最短路徑分支度隱 私保護，當新增連結時必須考量到每一對內的最短路徑是否受到更動，其計算 的複雜度與計算時間大大的增加。
另外，在本研究中仍可朝許多方向繼續延伸探討。第一點，目前本研究仍 以無向圖為主要研究的圖形，在未來我們將針對有向圖，持續研究試圖找出適 合有向圖的最短路徑隱私保護方法。第二點，未來可以試圖針對多對起、終點 對的最短路徑，找出多對起、終點對的最短路徑隱私保護方式，並且能夠提出 有效率的隱私保護方法。
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