David Rogers, Stu Andrzejewski, Kelly Desmond, Brad Garrod

 Receiving correct data  Communicating across network nodes accurately  Proper operation EKG graphs

Malicious Nodes Environmental Factors Insufficient Node Power

 Can destroy… ◦ Health/Lives  Air Pollution ◦ Equipment  Automobile ◦ Environment  Forest Fire Overall failing sensors can lead to millions of dollars in damage!

1.Configure a sensor network 2.Collect metrics about the network 3.Create human/network interface 4.Analyze correlations between metrics and node failure 5.Validate metrics and test for accuracy

1.Configure a sensor network A.Define network topology B.Identify vital components of sensor hardware C.Select sensor network hardware 2.Collect metrics about the network 3.Create human/network interface 4.Analyze correlations between metrics and node failure 5.Validate metrics for accuracy

 Mesh Topology ◦ Nodes communicate directly to other nodes without the need of a cluster head 1A. Network topology  Star Topology ◦ Cluster head controls data communication between nodes Advantages Better performance Benefits from centralization Isolation of nodes Simple Disadvantages Centralization dependency Expensive Central hub failure = network failure Advantages Self- healing Less traffic load Isolation of node faults Disadvantages Complexity Installation Price

 What kinds of information from the sensor would be useful to understand how well they are functioning? ◦ Battery life ◦ Current draw ◦ RF transmission power ◦ Received signal strength ◦ Processor load ◦ Memory utilization

 Powercast P2110-EVAL  Features ◦ Low-power ◦ Battery-free (RF Power) ◦ Pre-loaded, custom firmware ◦ Temperature, Humidity, and Light Sensors ◦ External Sensor Port ◦ RSSI Calculation ◦ USB interface for power and data  SunSPOT  Features ◦ Embedded Development Platform ◦ Extremely flexible hardware and software package ◦ Easy to program - Java top to bottom ◦ Connected – Wireless Communication ◦ Mobile & Secure ◦ Built in Lithium Ion battery charged through USB ◦ Able to sense and affect surroundings ◦ Built-in high grade ECC public key cryptography

1.Configure a sensor network 2.Collect metrics about the network A.What to monitor? 3.Create human/network interface 4.Analyze correlations between metrics and node failure 5.Validate metrics for accuracy

2A. What to monitor?  External ◦ Humidity ◦ Temperature ◦ Light ◦ Sound ◦ Motion ◦ Pressure ◦ Vibration ◦ Electrical Fields  Internal ◦ Current Draw ◦ Battery Life ◦ Voltage Reported ◦ RF Transmission ◦ Received Signal Strength ◦ Channel Availability ◦ Processor Load ◦ Memory Utilization (RAM)

1.Configure a sensor network 2.Collect metrics about the network 3.Create human/network interface A.Identify ideal communication protocol B.Create graphical user interface 4.Analyze correlations between metrics and node failure 5.Validate metrics for accuracy

 Must be able to communicate with sensors remotely  IEEE ◦ Includes ZigBee, Bluetooth, Wifi ◦ Uses CSMA/CA for secure communications  Nodes only transmit when the channel is idle ◦ Devices also include power management functions such as link quality and energy detection.

 Create user-friendly display ◦ Handles all incoming data packets from sensor nodes behind the scenes  The data will be displayed in a way for easy evaluation of the sensor data stream and network health ◦ Alerts the operator when failures have occurred or are occurring

1.Configure a sensor network 2.Collect metrics about the network 3.Create human/network interface 4.Analyze correlations between metrics and node failure 5.Validate metrics for accuracy

 Determine the most important metrics that identify node failure  Algorithms for detecting malfunctioning nodes ◦ Majority Voting ◦ Thresholding ◦ Weighted average  Understanding associations between multiple metrics ◦ Attempting to measure current draw while the sensor is transmitting back to the cluster head

1.Configure a sensor network 2.Collect metrics about the network 3.Create human/network interface 4.Analyze correlations between metrics and node failure 5.Validate metrics for accuracy

 Design a test plan to ensure a high quality health diagnostic ◦ Series of controlled experiments  Statistically validate chosen algorithms ◦ Reduce false positives and false negatives

 Monitoring sensor health is vital for proper function of a wireless sensor network  Many external and internal factors attribute to sensor node failure  By designing algorithms and a test plan to systematically validate failures, important metrics relating to the health of a wireless sensor network can be determined