1. Lab 3 Routing in Sensor Networks
Andreas Larsson

2. Part 1 Sensor Networks -- General
* The idea of sensor networks - massive distributed system
* Deployment
* Setting up the network
* The nodes themselves
* Usage patterns of sensor networks
* Examples of current uses

3. What is a sensor network?
”A sensor network, is a network of small computers placed in an area that we want to collect information from. The computers sense the environment and store, process and/or communicate this information”
* The idea of sensor networks – A massive distributed system
A general quick and easy introduction with some nice picture

4. Big range of Sensor Nodes
Table from CY Chong, SP Kumar, BA Hamilton - Proceedings of the IEEE, 2003

5. Deployment
“Sensor networks may be deployed in many different ways. A good way to see it is deployment from the air”
The “worst” case => The “general” case
We don’t know:
Where they end up
Which nodes can communicate with each other
Which nodes end up in the network
Can die in the fall
Can end up in a position where they cannot communicate with anyone
Battery changes tor practical (many cases):
Battery life is very important
(Often) Need of refilling the network
How sensor networks are deployed.
Picture of nodes being thrown out from a helicopter or something like that.
Stressing that in the general case we cannot control exactly where nodes end up.

6. Setting up the network
“So after deployment we have nodes over an area without knowing exactly which node is where. Therefore it is up to the nodes to set up a network among themselves and initialize the application they are going to run.”
Sensor Network = Ad Hoc Network

7. MicaZ Sensor Node CPU 7MHz Program Memory 128 kB RAM 4 kB
Storage Memory
512 kB
Bandwidth
250 kBps
Indoor Range
20-30 m
Outdoor Range m
Battery Life
Full operation at all times
50 h
Sensor limitations:
Limited computation capacity
Limited memory capacity
Limited storage capacity
Limited battery capacity
=>
Normal algorithms often unpractical
Ffew
fewfe

8. Usage patterns Sleeping The Main Task Auxiliary Tasks Data gathering
Data aggregation
Data communication
Auxiliary Tasks
Synchronization
Security

9. Examples of uses Utility Research Structural health monitoring
Agriculture
Parking space guidance/monitoring
Research
Volcanos
Permafrost
Animal behaviour

10. Permasense

11. COMMONSense

12. The Stork Bridge
Transition: These are not only general examples. Detecting volcano eruptions, earthquakes, tsunamis, problems with important infrastructure are significant for crisis management whether there is a malicious intent behind it or not.