71 lines
1.8 KiB
Markdown
71 lines
1.8 KiB
Markdown
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- Large number of heterogeneous devices
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- Spread physically
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- Ability to join and leave
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- Process data in-network or send directly
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# Challenges
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- Fault tolerance
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- Nodes can
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- Get damaged
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- Run out of power
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- Lose comms
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- Redundant deployment
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- Lifetime
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- Limited energy supply
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- Replacing sometimes not practical
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- Underwater
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- Large/remote field deployments
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- Energy efficient a necessity
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- Scalability
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- WSM can have lots of nodes
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- Architectures and protocols need to scale
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- Densities
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- Density of network can vary
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- Granularity
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- Coverage
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- Different applications warrant different numbers
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- Range of nodes
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- Space and time requirement
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- Not necessarily homogenous density throughout
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- Need to handle this
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- Programmability
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- Flexible nodes with changing tasks
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- Changeable programs during operation
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- Maintainability
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- WSN and environment can change
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- Adaptable system
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- Changing operational parameters
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- To increase energy efficiency for example
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# Node Types
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- Sensor
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- Low power
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- Sensing, memory, processor, radio
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- Resource-constrained
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- Sink
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- Another sensor node
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- Or different wireless node
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- Normally more powerful/better resources
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- Gateway
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- Bridge IoT and internet networks
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- More powerful
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- Can have
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- Service representation
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- Cache/storage
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- Discovery
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# Application Types
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- Event detection
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- Reporting event occurrences
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- Reporting abnormalities
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- May need collaboration with other nodes
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- Defining events and classification difficult
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- Periodic measurements
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- Sense something and report
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- Period is application-dependent
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- Approximation and pattern detection
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- Sense messages in space and time
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- E.g. combine wind, light, heat to detect forest fires
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- Tracking
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- Source of event is mobile
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- Event updates with location information
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