由於無線網路的快速發展，在漫遊服務的過程中，安全問題也隨之增加，例如:行動裝置與基地台之間的非法存取等。因為基地台的訊號範圍及強度受距離的限制，故行動裝置在使用漫遊服務時需透過不同的基地台存取網路。為了確保行動裝置與基地台雙方的合法性及通訊安全，同時降低基地台切換時造成網路服務的延遲，本研究提出了一套漫遊節點鑑別的機制，透過沃羅諾伊圖(Voronoi Diagram)來規劃基地台的位置及負責的訊號範圍，應用聚合簽章(Aggregate Signature)使基地台能夠追蹤行動裝置的鑑別記錄並確認鑑別訊息之合法性，確保整個過程參與者的合法性。

As the wireless network advances, many security issues have come into light when using roaming services such as illegal access of mobile devices or authentication centers. Due to signal strength and range restrictions of authentication centers, a mobile device may need to switch between different authentication centers while using the roaming service. To ensure the validity of both the mobile device and the authentication server and the security of the communication while maintaining low latency when switching between authentication centers, this study purposes a roaming node authentication scheme. This authentication scheme applies the Voronoi Diagram to plan the location of the authentication centers.
Furthermore, Aggregate Signatures are used to let mobile devices record every authenticated centers, this allows future authentications to verify the validity of the mobile device through previously authenticated centers.

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