Integration of Sensor Networks with Mobile Devices

1

• Integration of Sensor Networks with Mobile Devices

Computer Science Department University College
London
Vladimir Dyo November 22, 2005
2
Outline

• Introduction
• Problem and Motivation
• Isolating Problems
• Expected Contribution
• Initial Research Results
• Conclusion

3
Data Dissemination in SensorNets

• The Concept
• Sensors, Sinks
• Tasks Dissemination, Aggregation, Streaming
• Limitation Energy, Low Reliability

4
Current Research

• Infrastructure
• Routing
• GPSR
• Clustering
• LEECH
• Data Dissemination and Aggregation protocols
• Directed Diffusion, TAG, Synopsys Diffusion
• Middleware
• Milan, TinyLime, Slime, EnviroTrack

5
Problem - I

• Existing solutions work with static sinks
• Very strong assumption
• Not Realistic
• Not Energy Efficient
• No Coverage
• Examples TinyDB, Cougar

6
Problem - II Example

• Static collection
• Energy consumption
• Congestion
• Reliability
• Not practical

Suggested Approach Mobile Collection
7
Solution Mobile Collection

• Technical Advantages
• Coverage, energy, disconnected operations,
  flexibility
• Application Potential
• Environmental monitoring, industrial and
  pervasive applications

• Not Well Researched
• M. Batalin, Coverage, Exploration and Deployment
  by a Mobile Robot and Communication Network
• A. Chakrabarty, Exploiting Predictable Observer
  Mobility For Power Efficient Sensor Network
  Configuration
• S. Bhattacharya, Energy-conserving Data
  Placement and Asynchronous Multicast in WSN

8
Isolating Problems

• Protocol Support
• Mobile Data Collection. Routing Data towards a
  mobile collector
• Spatial Queries and Distributed Index
• select locations where (temp gt 30) OR (humidity gt
  0.4) within 30km from (X,Y)
• Middleware
• Defining Primitives
• Implementing Protocols

9
Expected Contribution

• Protocols
• Data Collection Protocol for Mobile Collectors
• Distributed Index for Spatial Queries in Sensor
  Networks
• Middleware for integration of sensor networks
  with mobile devices
• Architecture
• Primitives
• Implementation

10
Evaluation

• Data Collection Protocol
• Performance analysis in ns-2 simulator
• Critical Metric total communication overhead
• Real traces from other projects
• Implementation in TSky motes
• Middleware
• Implementation
• Real Deployment
• Climate and wildlife monitoring (in collaboration
  with Oxford zoologists)
• Micro-climate monitoring (UCL campus)

11
Initial Results

• Adaptive Distributed Indexing for Spatial Queries
  in Sensor Networks.
• V. Dyo and C. Mascolo. In IEEE Proceedings of 8th
  International Workshop on Mobility in Databases
  and Distributed Systems (co-located with DEXA05).
  August 2005, Copenhagen, Denmark. IEEE Computer
  Society Press

12
Proactive Reactive Mode
600 query/hour
Total 3601
Total 2400
Proactive 1
Proactive 3600
Total 1201
Reactive 1200
Reactive 1200
13
Future work on Index

• Data Resolution
• High update rates ? High Power Consumption
• Low response
• Low latency ? High Power Consumption
• Trade-off between
• Data resolution/response latency
• Total energy consumption

14
Conclusion

• Interesting problem
• Isolating issues
• Initial results

15
Questions

• Vladimir Dyo
• v.dyo_at_cs.ucl.ac.uk