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SNoDSNoDSensor Networks on Sensor Networks on

DefenseDefenseTeam Members:Team Members:

Kaustubh SupekarKaustubh SupekarGaurav SharmaGaurav SharmaDeepti AgarwalDeepti Agarwal

Aditya BarveAditya BarveBrijraj VaghaniBrijraj Vaghani

Seema JoshiSeema JoshiDebashis HaldarDebashis HaldarGautam KaushalGautam Kaushal

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Smart Dust eh!!!Smart Dust eh!!!

The particles of dust that could be The particles of dust that could be watching you .watching you .

Smart Dust is the brainchild of Smart Dust is the brainchild of Associate Professor Kris Pister and Associate Professor Kris Pister and Professor Randy H. Katz, who are Professor Randy H. Katz, who are currently working at the University currently working at the University of California, Berkeley of California, Berkeley

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Techie definitionTechie definitionSmart Dust Sensor (also known as a Smart Dust Sensor (also known as a sensor motesensor mote) is ) is a tiny wireless micro-electromechanical sensor a tiny wireless micro-electromechanical sensor (MEMS) packed into a cubic millimeter speck that (MEMS) packed into a cubic millimeter speck that can detect anything from light to vibrations.can detect anything from light to vibrations.

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Mote ConstraintsMote Constraints

Power, size and costPower, size and cost

These get translated toThese get translated to– Slow clock cycles of the micro controller.Slow clock cycles of the micro controller.– Less memory.Less memory.– Smaller number of hardware controllers.Smaller number of hardware controllers.

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MOTE SpecificationsMOTE SpecificationsTwo Board SandwichTwo Board Sandwich– CPU/Radio boardCPU/Radio board– Sensor Board: temperature, lightSensor Board: temperature, light

SizeSize– Mote: 1Mote: 11 in1 in– Pocket PC: 5.2Pocket PC: 5.23.1 in3.1 in

CPUCPU– Mote: 4 MHz, 8 bitMote: 4 MHz, 8 bit– Pocket PC: 133 MHz, 32 bitPocket PC: 133 MHz, 32 bit

MemoryMemory– Mote: 512 B RAM; 8K ROMMote: 512 B RAM; 8K ROM– Pocket PC: 32 MB RAM; 16 MB ROMPocket PC: 32 MB RAM; 16 MB ROM

RadioRadio– 900 Hz, 19.2 kbps900 Hz, 19.2 kbps– Bluetooth: 433.8 kbpsBluetooth: 433.8 kbps

Lifetime (Power)Lifetime (Power)– Mote: 3-65 daysMote: 3-65 days– Pocket PC: 8 hrsPocket PC: 8 hrs

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Sensor NetworkSensor NetworkA collection of sensor motes that A collection of sensor motes that perform autonomous sensing to form perform autonomous sensing to form the basis of a massively integrated the basis of a massively integrated sensor network which sends some sensor network which sends some useful information to a base station.useful information to a base station.

Some examples:Some examples: Environmental sensor networks to detect and Environmental sensor networks to detect and

monitor environmental changes.monitor environmental changes. Wireless surveillance sensor networks for Wireless surveillance sensor networks for

providing security in a shopping mall, parking providing security in a shopping mall, parking garage, etc. garage, etc.

Military sensor networks to detect enemy Military sensor networks to detect enemy movements, the presence of hazardous movements, the presence of hazardous

material.material.

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Sensor Vs Ad-Hoc Sensor Vs Ad-Hoc NetworksNetworks

The number of sensor nodes in a sensor network are The number of sensor nodes in a sensor network are much more than in an ad-hoc network.much more than in an ad-hoc network.Sensors act with other sensors in a restricted Sensors act with other sensors in a restricted vicinity. vicinity. The topology of a sensor network changes more The topology of a sensor network changes more frequently.frequently.Sensor nodes mainly use a broadcast paradigm, Sensor nodes mainly use a broadcast paradigm, whereas most ad-hoc networks are based on a point-whereas most ad-hoc networks are based on a point-to-point communication to-point communication Sensors are more constrained in memory and Sensors are more constrained in memory and energy compared to ad-hoc networks. energy compared to ad-hoc networks. Sensors interact with physical environment, they Sensors interact with physical environment, they experience Task Dynamics.experience Task Dynamics.

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Our AimOur Aim

Deploy a large number of sensor motes to form Deploy a large number of sensor motes to form a network to monitor movements of human a network to monitor movements of human beings in a terrain.beings in a terrain.The sensor motes communicate and co-ordinate The sensor motes communicate and co-ordinate efficientlyefficiently to establish an approximate count of to establish an approximate count of the number of human beings in that terrain.the number of human beings in that terrain.

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RequirementsRequirements

Large number of sensors which Large number of sensors which remain stationary after random remain stationary after random deployment.deployment.

Low energy usage (Computationally Low energy usage (Computationally light execution and minimal amount light execution and minimal amount of energy transmission)of energy transmission)

Self-organizing networkSelf-organizing network

Collaborative signal processing (Data Collaborative signal processing (Data aggregation)aggregation)

SecuritySecurity

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Human detectionHuman detection

PIR sensorsPIR sensorsPassive Infrared Sensors detect infra-red heat energy emitted by humans. Triggering occurs when they detect a change in infrared levels, as and when a warm object moves in or out of range of a sensor. They are quite resistant to false triggering.

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Salient FeaturesSalient Features

A A localized clustering algorithmlocalized clustering algorithm that that contributes to scalability, robustness and efficient contributes to scalability, robustness and efficient utilization of resources.utilization of resources.

A A routing algorithmrouting algorithm that adapts itself to the that adapts itself to the dynamics of the network and changes in the dynamics of the network and changes in the clusters.clusters.

A A data aggregation algorithmdata aggregation algorithm to fuse data to fuse data from multiple sensors within a cluster.from multiple sensors within a cluster.

SecuritySecurity features that ensure only authorized features that ensure only authorized users are granted access to the network and only users are granted access to the network and only those messages that weren’t altered in transit are those messages that weren’t altered in transit are accepted.accepted.

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ClusteringClustering

Allows to efficiently co-ordinate local Allows to efficiently co-ordinate local information and thus contribute to information and thus contribute to scalability, robustness and efficient scalability, robustness and efficient utilization of resources.utilization of resources.

Each cluster is formed during Each cluster is formed during bootstrap and all the members of a bootstrap and all the members of a cluster elect a cluster head, which cluster elect a cluster head, which performs data aggregation and performs data aggregation and routing for the cluster.routing for the cluster.

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All sensors start advertising presence within a All sensors start advertising presence within a predefined broadcast range and start WAIT TIMER.predefined broadcast range and start WAIT TIMER.

By the end of the WAIT TIME all the sensors would have By the end of the WAIT TIME all the sensors would have received advertisements from the sensors within its received advertisements from the sensors within its broadcast range. All sensors then start their PROMOTION broadcast range. All sensors then start their PROMOTION TIMER, which is inversely proportional to the energy level TIMER, which is inversely proportional to the energy level of the sensor and number of advertisements it receivedof the sensor and number of advertisements it received..

After PROMOTION TIMER expires, if a sensor hasn’t After PROMOTION TIMER expires, if a sensor hasn’t received any other sensor’s advertisement received any other sensor’s advertisement declaring itself as the declaring itself as the Cluster HeadCluster Head, then the , then the sensor promotes itself as the cluster head.sensor promotes itself as the cluster head.

All cluster heads send advertisements to the sensors All cluster heads send advertisements to the sensors from which they received presence advertisements.from which they received presence advertisements.

All non-cluster heads choose their cluster All non-cluster heads choose their cluster head and form clusters.head and form clusters.

Cluster headsCluster heads

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RoutingRoutingBase stationBase station

Base station sends a message within a limited Base station sends a message within a limited range so that only nearest cluster heads range so that only nearest cluster heads receive it.receive it.

w01w01w02w02 w03w03

w04w04Level 0Level 0

All the cluster heads receiving this message set All the cluster heads receiving this message set themselves as Level 0 members and assign weight to themselves as Level 0 members and assign weight to themselves based on the received RF signal strength themselves based on the received RF signal strength from the base station and send back from the base station and send back acknowledgements.acknowledgements.

Level 0 cluster heads now propagate another Level 0 cluster heads now propagate another message within a limited range for other cluster message within a limited range for other cluster heads.heads.

Only the clusters not within Level 0 listen to those Only the clusters not within Level 0 listen to those messages and again calculate their own weight messages and again calculate their own weight based on the received messages’ signal strength. based on the received messages’ signal strength. These clusters are at Level 1.These clusters are at Level 1.

w11w11

Level 1Level 1w12w12

(W01*w11 + w02*w12) / 2(W01*w11 + w02*w12) / 2

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Communication amongst Communication amongst SensorsSensors

Since all sensors within a single cluster Since all sensors within a single cluster operate at the same frequency, provisions operate at the same frequency, provisions have to be made such that the signals do have to be made such that the signals do not interfere with each other .We not interfere with each other .We overcome this problem by using overcome this problem by using CSMA/CACSMA/CA..

Similarly even the cluster heads when Similarly even the cluster heads when sending information to a lower level or to sending information to a lower level or to the base station use the same technology the base station use the same technology

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Future WorkFuture Work

Implementation of Security FeaturesImplementation of Security FeaturesData Aggregation of information from Data Aggregation of information from various sensors.various sensors.Fine tuning of routing and clustering Fine tuning of routing and clustering algorithms.algorithms.Parallel processing of Clustering and Parallel processing of Clustering and Routing algorithms, the current version Routing algorithms, the current version works sequentiallyworks sequentiallySimulation of the algorithms to test their Simulation of the algorithms to test their validity.validity.

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ApplicationsApplications

Location and quantity detection in a Location and quantity detection in a Warehouse.Warehouse.

Disaster detection and recovery Disaster detection and recovery which today by comparison is very which today by comparison is very human intensive.human intensive.

2020

Q&AQ&A

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