PowerPoint PresentationThe need for Data Dissemination and FusionSlide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21Slide 22Directed Diffusion [Intanagonwiwat+ 2000]Directed DiffusionSlide 25Slide 26Slide 27Slide 28Slide 29Slide 30Slide 31ReferencesData Dissemination and FusionIn Sensor NetworksThe need for Data Dissemination and Fusion–Energy efficiency is an essential factor; therefore, short-range hop-by-Energy efficiency is an essential factor; therefore, short-range hop-by-hop communication is preferred over direct long-range communication hop communication is preferred over direct long-range communication to the destinationto the destination–Since sensor network contains large amount of data for the end user, Since sensor network contains large amount of data for the end user, methods of combining or aggregating data into small set of information methods of combining or aggregating data into small set of information is necessary and contributes to energy savingsis necessary and contributes to energy savings–Data aggregation (aka data fusion) can combine unreliable data Data aggregation (aka data fusion) can combine unreliable data readings to produce accurate signal by improving the common signal readings to produce accurate signal by improving the common signal and reducing the noiseand reducing the noise–LEACHLEACH (Low-Energy Adaptive Clustering Hierarchy) is a clustering-based (Low-Energy Adaptive Clustering Hierarchy) is a clustering-based protocol that utilizes the randomized rotation of local cluster base stations protocol that utilizes the randomized rotation of local cluster base stations to evenly distribute the energy load within the network of sensorsto evenly distribute the energy load within the network of sensors–It is a distributed, does not require any control information from base station It is a distributed, does not require any control information from base station (BS) and the nodes do not need to have knowledge of global network for (BS) and the nodes do not need to have knowledge of global network for LEACH to functionLEACH to function–The energy saving of LEACH is achieved by combining compression with The energy saving of LEACH is achieved by combining compression with data routingdata routing–Key features of LEACH include:Key features of LEACH include:Localized coordination and control of cluster set-up and operationLocalized coordination and control of cluster set-up and operationRandomized rotation of the cluster base stations or clusterheads and their Randomized rotation of the cluster base stations or clusterheads and their clustersclustersLocal compression of information to reduce global communicationLocal compression of information to reduce global communicationEnergy-Efficient Communication Protocol Architecture for Wireless Microsensor Networks (LEACH Protocol)[Heinzelman+ 2000, 2002]–Considered microsensor network has the following characteristics:Considered microsensor network has the following characteristics:The base station is fixed and located far from the sensorsThe base station is fixed and located far from the sensorsAll the sensor nodes are homogeneous and energy constrainedAll the sensor nodes are homogeneous and energy constrained–Communication between sensor nodes and the base station is expensive and no Communication between sensor nodes and the base station is expensive and no high energy nodes exist to achieve communicationhigh energy nodes exist to achieve communication–By using clusters to transmit data to the BS, only few nodes need to transmit for By using clusters to transmit data to the BS, only few nodes need to transmit for larger distances to the BS while other nodes in each cluster use small transmit larger distances to the BS while other nodes in each cluster use small transmit distancesdistances–LEACH achieves superior performance compared to classical clustering algorithms LEACH achieves superior performance compared to classical clustering algorithms by using adaptive clustering and rotating clusterheads; assisting the total energy of by using adaptive clustering and rotating clusterheads; assisting the total energy of the system to be distributed among all the nodesthe system to be distributed among all the nodes–By performing load computation in each cluster, amount of data to be transmitted to By performing load computation in each cluster, amount of data to be transmitted to BS is reduced. Therefore, large reduction in the energy dissipation is achieved BS is reduced. Therefore, large reduction in the energy dissipation is achieved since communication is more expensive than computationsince communication is more expensive than computationLEACHAlgorithm OverviewAlgorithm Overview–The nodes are grouped into local clusters with one node acting as the local base The nodes are grouped into local clusters with one node acting as the local base station (BS) or clusterhead (CH)station (BS) or clusterhead (CH)–The CHs are rotated in random fashion among the various sensorsThe CHs are rotated in random fashion among the various sensors–Local data fusion is achieved to compress the data being sent from clusters to the Local data fusion is achieved to compress the data being sent from clusters to the BS; resulting the reduction in the energy dissipation and increase in the network BS; resulting the reduction in the energy dissipation and increase in the network lifetimelifetime–Sensor elect themselves to be local BSs at any any given time with a certain Sensor elect themselves to be local BSs at any any given time with a certain probability and these CHs broadcast their status to other sensor nodesprobability and these CHs broadcast their status to other sensor nodes–Each node decided which CH to join based on the minimum communication energyEach node decided which CH to join based on the minimum communication energy–Upon clusters formation, each CH creates a schedule for the nodes in its cluster Upon clusters formation, each CH creates a schedule for the nodes in its cluster such that radio components of each non-clusterhead node need to be turned OFF such that radio components of each non-clusterhead node need to be turned OFF always except during the transmit timealways except during the transmit time–The CH aggregates all the data received from the nodes in its