在無線感測網路中，各節點間常利用彼此將訊息傳送至接收端。然而，無線感測網路通常會佈署在一些傳輸困難的嚴苛環境裡，而嚴苛的環境使得封包遺失率上升。從網路的角度來看，封包的傳輸效能是無線傳輸中最基本的要求之一。傳輸效能的好壞會進而影響到網路中資料採集效能的好壞，因此，一個能診斷在無線感測網路中封包丟失的工具是非常有用的。診斷無線感測網路封包傳輸問題的相關研究有很多，大多數的研究都採用主動的方式，像是在感測器中安裝偵錯代理，並週期性的回報此感測器狀況到主要接收端中。然而，主動的方式會耗費多餘的資源去傳送狀態資訊，對資源有限以及對傳輸量敏感的感測網路只會造成更多負擔。除主動的方式之外，我們可以選擇利用被動的方式，檢查主要接收端的資料封包，來判斷造成封包丟失的原因。在一個近期的研究中[1]，作者提出了輕量的封包標記方法。在不增加多餘的狀態封包下，蒐集有關封包丟失的隱藏資訊。在本篇論文中，我們的目標是根據上述的研究，建立一個實際的無線感測網路診斷工具。這個工具可以追蹤無線感測網路中封包的傳送效能以及偵測封包丟失的狀況，同時也允許使用者可以從主要接收端去觀察最新的網路狀態，並標示出發生封包丟失的節點。在這論文中將展示此工具的實作，並用真實的案例研究它的用法與效能。

[1] Mo Li Kebin Liu, Yunhao Liu, “Passive diagnosis for wireless sensor networks”, In proceedings of the 6th ACM conference on embedded network sensor systems, pp. 113 – 126, 2010.
[2] A. Woo D. Culler D. Estrin D. Ganesan, B. Krishnamachari and S. Wicker, “Complex behavior at scale: An experimental study of low-power wireless sensor networks”, in Technical report UCLA/CSD-TR 02-0013, 2002.
[3] N. Xu, “A survey of sensor network application”, Tech. Rep.
[4] J. Johnson J. Lees G. Werner-Allen, K. Lorincz and M. Welsh, “Fidelity and yield in a volcano monitoring sensor network”, in OSDI ’06 Proceedings of the 7th symposium on
operating systems design and implementation. 2006, pp. 381 – 396, USENIX Association Berkeley, CA, USA 2006.
[5] J. Stankovic T. Abdelzaher L. Luo R. Stoleru T. Yan L. Gu J. Hui T. He, S. Krish-namurthy and B. Krogh, “Energy-efficient surveillance system using wireless sensor networks”, in proc. of ACM MobiSys, 2004.
[6] K. Chintalapudi D. Ganesan A. Broad R. Govindan N. Xu, S. Rangwala and D. Estrin,“A wireless sensor network for structural monitoring”, In proc. of ACM SenSys, 2004.
[7] L. Girod R. Kapur E. Kohler N. Ramanathan, K. Chang and D. Estrin, “Sympathy for the sensor network debugger”, in proc. of ACM SenSys, 2005.
[8] A. Cerpa T. Stathopoulos N. Ramanathan L. Girod, J. Elson and D. Estrin, “Emstar: a software environment for developing and deploying wireless sensor networks”, in
proceedings of the USENIX annual technical conference, Boston, MA, 2004.
[9] Glenn Durfee Jessica Staddon, Dirk Balfanz, “Efficient tracing of failed nodes in sensor networks”, In proceedings of the ACM WSNA’02, pp. 122 – 130, September 2002.
[10] Rohan Bhindwale Ahmed Helmy Sapon Tanachaiwiwat, Pinalkumar Dave, “Secure locations: routing on trust and isolating compromised sensors in location-aware sensor networks”, In proceedings of the ACM SenSys’03, pp. 324 – 325, 2003.
[11] Wei Gong; Kebin Liu ; Yunhao Liu ; Xibin Zhao ; Ming Gu, “Directional diagnosis for wireless sensor networks”, in Distributed computing in sensor systems and workshops (DCOSS), 2011.
[12] Robert Szewczyk Joseph Polastre and David Culler, “Telos: Enabling ultra-low power wireless research”, in IPSN ’05 Proceedings of the 4th international symposium on
information processing in sensor networks. 2005, number 48, IEEE Press Piscataway, NJ, USA 2005.