無線感測網路通常被佈置於廣大的環境中，由於開放式通訊的特性，攻擊者可以利用竊聽技術找到來源節點或基地台位置，進而造成安全上的疑慮。過去的位置隱私方案，大多只保護來源節點或是基地台位置；另一方面，多數的方案缺少考慮資料重要性的差異程度，若將各種資料視為同等重要，則會浪費過多資源保護重要性較低的資料。

本論文考慮資料重要性的差異，以保護來源節點及基地台位置為目標。我們提出兩種節點隱藏方案用於無線感測網路，分別為廣播的節點分級式隱藏方案與足量的節點分級式隱藏方案。這兩種方案皆產生假節點的方式對抗區域性攻擊者，保護來源節點及基地台的位置隱私。

透過模擬結果顯示，在對抗區域性攻擊者上，我們提出的方案相較於先前研究更能有效保護節點位置。在通訊成本上，足量的節點分級式隱藏方案能花費較少資源產生假節點。

Since wireless sensor networks (WSNs) are often deployed in open environments,attackers can eavesdrop communications between nodes to identify the locations of sources and destinations of messages, which causes privacy and security concerns. Although there exist studies on protecting location privacy of communication endpoints in WSNs, most work tend to overspend resources to protect unimportant data because of lacking data importance considerations.

This paper proposes two schemes on protecting end-to-end location privacy
in WSNs that take data importance levels into account, namely Broadcast-based Hierarchical Hidden Nodes Scheme (HHNB) and Sufficiency-based Hierarchical Hidden Nodes Scheme(HHNS). Both schemes create forged identities to hide the locations the source node and the destination node of a message from a local eavesdropper.

The simulation results show the proposed methods provide better protection
against local eavesdropper than previous researches on end-to-end location privacy in a WSN. Also, HHNS induces less communication costs in generating
forged identities.

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