無線感測網路最主要的功能就是透過感測器將所感測到的資料傳輸回基地台供分析與處理。大部分感測器均離基地台有一段距離。所以訊息必須透過中間感測器來幫忙轉送。由於感測器的電力資源有限，因此將訊息透過適當的路由機制所建立的路徑來傳送至基地台會較不指定路徑的傳輸方式更省電力。且由於訊息在傳輸的過程中是透過無線傳輸的方式，相較於傳統有線網路訊息更容易遭到竊聽、竄改等攻擊。因此如何建立路由路徑並確保訊息在路徑傳輸中的安全性乃相當重要。除此之外，在訊息傳輸機制中相當重要的一環就是訊息傳輸的可靠性，亦即訊息成功送達目的地的比率。可靠性的高低不僅會受到網路品質的影響，同時在面臨惡意攻擊者時，亦會造成可靠性的下降。最常見的一種攻擊即為選擇性轉送攻擊。這種攻擊會大幅地降低訊息傳輸的可靠性。本論文提一安全感測網路傳輸技術，每個感測器可以建立多條到達基地台的路由路徑，並透過相關的金鑰對訊息做加密與訊息鑑別碼以確保了資料在傳輸過程中的機密性與完整性。同時透過監督機制來監控訊息的傳輸狀態，可降低不良網路狀態亦或是攻擊者發動的選擇性轉送攻擊對於訊息傳輸所造成的影響。 The main function of wireless sensor networks is to let sensors sense data and send data back to the base station. Most of sensor nodes need the intermediate nodes to help them relay the data. In order to limit the power consumption of the sensor node, we usually use the routing paths created by the proper routing scheme to transmit the data. Because all transmission is done through wireless communications, the data has more chance to be sniffed or tampered with than through wire transmission. So, it is important to establish the routing paths and to ensure the security of the data in the transmission. Besides, another important issue of the data dissemination scheme is the reliability of the transmission. It is not only affected by the quality of the network, but also in face to the attacker. The common attack is selective forwarding attack. This kind of attack will reduce the reliability of the transmission substantially. In our proposed scheme, we let all nodes generate multiple paths back to the base station, and we use the encryption and message authentication code to keep the confidentiality and integrity of the data. We also monitor the transmission status through our monitor method. So, our scheme maintains the high reliability even under the selective forwarding attack caused by the attacker.
