1. A Fault Management Architecture For Wireless Sensor Network 學生：林忠成 學號： 79864007 Date : 2010/05/10

2. Outline Introduction Requirements for system design A new cellular fault management architecture Management process Conclusion

3. Introduction fault tolerance is the ability to maintain sensor networks functionalities without any interruption due to sensor nodes failure. In order to design efficient fault management architecture for WSN, various faults association with WSN required to be understood.

4. Requirements for system design Scalability Energy Efficiency Lightweight Operation Local detection and Management

5. A new cellular fault management architecture Cellular architecture In this architecture we divide the network into a virtual grid of cells. Cell manager,Gateway node and Common node Group manager

6. node 1 到 node 10 在彼此的傳輸範圍之內, 因此可以把它切分成兩 個 cell

7. Cell A 內的所有 node 都可以跟 cell B 內的所有 node 交換資訊 在分好所有的 cell 之後,cell 裡的 node 都傳送出一個 discovery message 包含 node ID,cell ID 和 energy level 然後比較出最高 energy level 的 node, 推選出來當做 cell manager, 然後再由 cell manager 向 cell 成員廣播要求訊息，以相同的方式選出一個 node 作為 gateway node Cell 跟 cell 之間透過彼此之間的 gateway node 來溝通傳遞訊 息

8. 多個 cell 可以結合成一個 group ，並由其中推選出一個 group manager

9. Management process Fault detection The fault detection process can be divided into: ＊ In-Cell fault detection ＊ Cell and Cell manager's fault detection & recovery

10. In-cell fault detection Cell manager send get messages to the associated common nodes and gateway node on regular basis and in return they send there updates. If the cell manager does not receive an update from any node then it send an instant message to the node and acquire about its status. If cell manager does not receive the acknowledge in a given time then declare it as a faulty node and pass this information to the rest of the network

11. Cell and Cell manager's fault detection & recovery Each cell manager sends health status information to its group manager through gateway node. If the gateway node does not receive the get message from its cell manager during updates cycle then it send a quick reminder to its cell manager and expect a quick reply but if it does not receive any reply then it consult common nodes and inform then about the failure of the cell manager and ask them to send there current ststus information. Upon receiving updates from common nodes,it appoints a new cell manager and informs it group members.

12. Conclusion it divided the network into a virtual grid,where each cell consists of a group of nodes.This supports scalability of the network and increase network life time. Most of existing solution used some type of central entity to perform fault management tasks but in our proposed solution,the aim is to perform fault detection locally and in distributed fashion.

13. Thank You