This document provides an overview of wireless sensor networks. It discusses what sensor networks are and their applications in areas like military, industry, science and more. It describes the constraints of sensor networks like limited battery power, storage and processing. It outlines several research challenges in sensor networks including energy efficiency, scalability, heterogeneity and self-configuration. The document also discusses various layers in the sensor network protocol stack from the physical layer to the application layer and highlights issues at each layer.
Network management in wireless sensor networks is critical due to their limited resources and ad hoc structure. It is important for three main reasons: to deploy adaptive and resource-efficient algorithms, enable collaboration between sensor nodes, and ensure full monitoring coverage of the target area. One key design issue is for transport protocol design, which must consider energy conservation, congestion control, reliability, and management given the constraints of wireless sensor networks.
NetSim (http://www.tetcos.com/) Best Network Simulator , provide wireless sensor network Based IEEE 802.15.4 Standard
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The document discusses cognitive radio architecture. It describes 5 perspectives of cognitive radio architecture:
1) Functions, components and design rules
2) The cognition cycle of observe, orient, plan, decide, and act
3) The inference hierarchy from atomic stimuli to context clusters
4) Architecture maps that show behaviors
5) Building cognitive radio architecture on software-defined radio architectures by adding computational intelligence and learning capabilities.
This document presents an energy aware QoS routing protocol for wireless sensor networks. It finds the least-cost path that meets end-to-end delay requirements for real-time data using a queuing model. The protocol calculates link costs and uses a k-least cost path algorithm to find candidate routes. It then determines the optimal path's r-value, which represents the ratio of real-time to non-real-time bandwidth on each link. Simulation results show the protocol can improve QoS metrics like end-to-end delay while increasing network lifetime.
Introduction
Background
WSN Design Issues: MAC Protocols, Routing Protocols, Transport Protocols
Performance Modeling of WSNs: Performance Metrics, Basic Models, Network Models
Case Study: Simple Computation of the System Life Span
Practical Example.
Routing protocols for wireless sensor networks face several unique challenges compared to other wireless networks. This document discusses routing challenges in wireless sensor networks and provides an overview of different routing protocol approaches, including flat routing, hierarchical routing, location-based routing, and QoS-based routing. It specifically describes two flat routing protocols: directed diffusion, which uses data negotiation and aggregation to reduce energy costs, and SPIN, which employs data description messages to avoid redundant transmissions through negotiation between sensor nodes.
How to put these nodes together to form a meaningful network.
How a network should function at high-level application scenarios .
On the basis of these scenarios and optimization goals, the design of networking protocols in wireless sensor networks are derived
A proper service interface is required and integration of WSNs into larger network contexts.
Routing protocols in wireless sensor networks face several unique challenges compared to other wireless networks. The document discusses these challenges and provides an overview of common routing protocol approaches in WSNs, including flat routing protocols like SPIN and Directed Diffusion, hierarchical routing protocols like LEACH, and location-based routing protocols. It also covers routing design issues specific to WSNs such as energy efficiency, data delivery models, fault tolerance, and quality of service.
Network management in wireless sensor networks is critical due to their limited resources and ad hoc structure. It is important for three main reasons: to deploy adaptive and resource-efficient algorithms, enable collaboration between sensor nodes, and ensure full monitoring coverage of the target area. One key design issue is for transport protocol design, which must consider energy conservation, congestion control, reliability, and management given the constraints of wireless sensor networks.
NetSim (http://www.tetcos.com/) Best Network Simulator , provide wireless sensor network Based IEEE 802.15.4 Standard
follow this link for more Details
http://www.tetcos.com/
The document discusses cognitive radio architecture. It describes 5 perspectives of cognitive radio architecture:
1) Functions, components and design rules
2) The cognition cycle of observe, orient, plan, decide, and act
3) The inference hierarchy from atomic stimuli to context clusters
4) Architecture maps that show behaviors
5) Building cognitive radio architecture on software-defined radio architectures by adding computational intelligence and learning capabilities.
This document presents an energy aware QoS routing protocol for wireless sensor networks. It finds the least-cost path that meets end-to-end delay requirements for real-time data using a queuing model. The protocol calculates link costs and uses a k-least cost path algorithm to find candidate routes. It then determines the optimal path's r-value, which represents the ratio of real-time to non-real-time bandwidth on each link. Simulation results show the protocol can improve QoS metrics like end-to-end delay while increasing network lifetime.
Introduction
Background
WSN Design Issues: MAC Protocols, Routing Protocols, Transport Protocols
Performance Modeling of WSNs: Performance Metrics, Basic Models, Network Models
Case Study: Simple Computation of the System Life Span
Practical Example.
Routing protocols for wireless sensor networks face several unique challenges compared to other wireless networks. This document discusses routing challenges in wireless sensor networks and provides an overview of different routing protocol approaches, including flat routing, hierarchical routing, location-based routing, and QoS-based routing. It specifically describes two flat routing protocols: directed diffusion, which uses data negotiation and aggregation to reduce energy costs, and SPIN, which employs data description messages to avoid redundant transmissions through negotiation between sensor nodes.
How to put these nodes together to form a meaningful network.
How a network should function at high-level application scenarios .
On the basis of these scenarios and optimization goals, the design of networking protocols in wireless sensor networks are derived
A proper service interface is required and integration of WSNs into larger network contexts.
Routing protocols in wireless sensor networks face several unique challenges compared to other wireless networks. The document discusses these challenges and provides an overview of common routing protocol approaches in WSNs, including flat routing protocols like SPIN and Directed Diffusion, hierarchical routing protocols like LEACH, and location-based routing protocols. It also covers routing design issues specific to WSNs such as energy efficiency, data delivery models, fault tolerance, and quality of service.
Routing protocols are essential for wireless sensor networks to efficiently transmit collected sensor data to data sinks. The document discusses several challenges in designing routing protocols for wireless sensor networks and surveys different routing techniques including flat, hierarchical, and geographic routing. It provides LEACH and PEGASIS as examples of hierarchical routing protocols that use clustering and data aggregation to reduce energy consumption.
Sensor Networks Introduction and ArchitecturePeriyanayagiS
This document provides an overview of sensor networks and wireless sensor network architectures. It begins with an introduction to wireless sensor networks and their components. It then discusses the topics, challenges, and enabling technologies for WSNs. The document outlines the architecture of a sensor node and its goals. It provides examples of WSN applications and discusses sensor network deployment considerations. Finally, it addresses the design challenges, operational challenges, and required mechanisms for WSNs to meet their requirements.
This document summarizes and compares three clustering algorithms for wireless sensor networks: LEACH, HEED, and PEGASIS. LEACH is the first protocol to use hierarchical routing to increase network lifetime. It forms clusters with local heads that collect data from members and transmit to the base station. HEED uses residual energy and network topology features to select distributed cluster heads. PEGASIS forms chains between sensors so each transmits to a close neighbor, avoiding hotspots. The document analyzes these algorithms and compares their effects on network lifetime.
The document presents an overview of QoS aware routing protocols for wireless sensor networks. It discusses the EQRS protocol which uses a link cost function and path discovery phase to establish multiple paths between nodes while considering energy efficiency and QoS metrics. It also briefly describes the SAR and DAST protocols, with SAR using a table-driven approach to create multiple paths from sensors to a sink node based on energy resources and packet priority, and DAST utilizing location information and remaining energy to select paths.
This document discusses power aware routing protocols for wireless sensor networks. It begins by describing wireless sensor networks and how they are used to monitor environmental conditions. It then classifies routing protocols for sensor networks based on their functioning, node participation style, and network structure. Specific examples are provided for different types of routing protocols, including LEACH, TEEN, APTEEN, SPIN, Rumor Routing, and PEGASIS. Chain-based and clustering routing protocols are also summarized.
This document discusses network topologies, switching, and routing algorithms. It defines different network topologies including mesh, star, bus, ring, tree, and hybrid topologies. It also describes hubs, switches, circuit switching, message switching, packet switching, datagram networks, and virtual circuit networks. For routing algorithms, it explains distance vector routing which uses hop count as the routing metric and link state routing which uses weighted metrics to calculate the shortest path.
Wireless LANs can be used for several applications, including extending a wired LAN to cover open or remote areas, connecting nearby buildings, providing mobile access to laptop users, and enabling temporary ad hoc networks. Wireless LANs use either infrared or radio frequency transmission and can be configured in various network topologies like peer-to-peer or with a central hub device. While infrared avoids licensing, it has limitations on range and ambient light interference, while radio frequency options operate in either licensed narrowband microwave spectra or unlicensed industrial, scientific and medical bands.
This document summarizes several energy-aware routing protocols for wireless sensor networks. It discusses classical approaches like flooding and gossiping and their deficiencies. It then describes the SPIN protocol which uses negotiations and metadata to adapt to resource constraints. Directed Diffusion is also covered, using interests, data messages, gradients, and reinforcement to set up multiple paths between sources and sinks. The document provides details on how these protocols establish and maintain paths while conserving energy in wireless sensor networks.
The document discusses routing protocols in wireless sensor networks. It outlines several key challenges for routing protocols including node deployment, network dynamics, energy conservation, fault tolerance, scalability, and hardware constraints. It then describes several common routing techniques used in wireless sensor networks, including proactive, reactive, and hybrid path establishment approaches, as well as flat, hierarchical, and location-based network structures. Finally, it discusses different protocol operations such as multipath routing, query-based routing, negotiation-based routing, and supporting quality of service metrics.
EC8702 adhoc and wireless sensor networks iv eceGOWTHAMMS6
This document outlines the syllabus for a course on Adhoc and Wireless Sensor Networks. It covers five units: (1) Introduction to Adhoc Networks and routing protocols, (2) Introduction to sensor networks and architectures, (3) Networking concepts and protocols for sensor networks, (4) Security issues in sensor networks, and (5) Sensor network platforms and tools. Some key topics discussed include characteristics of adhoc networks, challenges in routing, components and applications of wireless sensor networks, and medium access schemes. The objectives are for students to learn the fundamentals and apply their knowledge to identify suitable protocols based on network requirements and understand security and transport layer issues in these networks.
This document discusses ad hoc and wireless sensor networks. It describes several applications of ad hoc networks including military operations, collaborative work, emergency response, and wireless mesh networks. It also discusses wireless sensor networks and their use in fields like healthcare, environmental monitoring, and more. Finally, it outlines some of the major challenges in designing routing protocols for ad hoc networks such as mobility, bandwidth constraints, and resource limitations.
The document discusses secure routing protocols for wireless sensor networks. It begins by describing the components and design challenges of wireless sensor networks, including limited resources and security issues. It then discusses various attacks on wireless sensor networks like spoofing, selective forwarding, and sinkhole attacks. The document analyzes several secure routing protocols that aim to prevent such attacks, including Distributed Security Framework, Multipath Data Transfer Protocol, Secure and Energy Efficient Disjoint Route, and Bio-inspired Self-Organized Secure Autonomous Routing Protocol. It concludes by discussing future work to develop a new routing approach with low energy consumption, high delivery ratio, and strong security against possible threats.
This document discusses wireless sensor networks and sensor node technology. It provides details on the basic components and functionality of wireless sensor nodes, including hardware components like sensors, processing units, and communication units. It also describes software subsystems like operating systems, sensor drivers, and data processing applications. The document outlines design constraints for wireless sensor networks and trends toward miniaturization and integration. It summarizes research efforts to develop new sensor technologies, arrayed sensor networks, and techniques for interpreting sensor data for decision-making.
This document summarizes various techniques for saving energy in wireless sensor networks. It discusses how sensor nodes consume power through transmission, reception, processing and idle listening. It then describes approaches like sleep-wake scheduling, MAC protocols like S-MAC and T-MAC, in-network processing, network coding and scheduled/contention-based communication protocols to minimize energy usage. The goal is to reduce unnecessary listening and maximize the time sensors spend in sleep mode to improve battery life for sensor network applications.
The document discusses the syllabus for the course EC8702 Adhoc and Wireless Sensor Networks. The syllabus covers topics like adhoc network routing protocols, sensor network architecture and design issues, transport layer and security protocols for adhoc and sensor networks, and programming platforms and tools. The course objectives are to learn the fundamentals of adhoc and sensor networks, apply routing algorithms, identify physical and MAC layer protocols, and describe transport layer and security issues. Upon completing the course, students will be able to explain adhoc and sensor network basics, apply routing algorithms, identify protocols, describe transport and security issues, and program sensor nodes.
A General Self Organized Tree Based Energy Balance Routing Protocol for WSN Sathish Silence
GSTEB is a self-organized tree-based energy-balance routing protocol for wireless sensor networks. It aims to prolong network lifetime by balancing energy consumption across nodes. In GSTEB, the base station selects a root node and broadcasts its ID. Then each node selects its parent in a way that minimizes its distance to the root while balancing energy levels. The network operates in rounds, where a routing tree is constructed and nodes transmit sensed data to the base station along the tree. GSTEB dynamically changes the root node between rounds to further balance energy usage among all nodes. Simulation results show GSTEB outperforms other protocols in balancing energy consumption and extending network lifetime.
Seismic sensors and networks in Hawaii monitor earthquakes and volcanoes on the Big Island. The USGS operates several types of seismic stations, including short period and broadband sensors. Other groups also operate stations, and data is shared. The network helps track earthquake activity and volcanic processes. Hawaii experiences large earthquakes that can cause tsunamis, making seismic monitoring important for hazards assessment and early warning. Efforts aim to expand the network and coordination to improve earthquake reporting and monitoring statewide.
This document discusses the potential applications of embedded networked sensing systems. It outlines several motivating applications including monitoring seismic structure response, tracking contaminant transport, and monitoring ecosystems and biocomplexity. For each application, it describes the relevant science goals and how embedded networked sensing could provide data to advance understanding. It also discusses some of the research challenges for these applications and outlines initial steps being taken. The document concludes by discussing enabling technologies for embedded networked sensing systems.
Routing protocols are essential for wireless sensor networks to efficiently transmit collected sensor data to data sinks. The document discusses several challenges in designing routing protocols for wireless sensor networks and surveys different routing techniques including flat, hierarchical, and geographic routing. It provides LEACH and PEGASIS as examples of hierarchical routing protocols that use clustering and data aggregation to reduce energy consumption.
Sensor Networks Introduction and ArchitecturePeriyanayagiS
This document provides an overview of sensor networks and wireless sensor network architectures. It begins with an introduction to wireless sensor networks and their components. It then discusses the topics, challenges, and enabling technologies for WSNs. The document outlines the architecture of a sensor node and its goals. It provides examples of WSN applications and discusses sensor network deployment considerations. Finally, it addresses the design challenges, operational challenges, and required mechanisms for WSNs to meet their requirements.
This document summarizes and compares three clustering algorithms for wireless sensor networks: LEACH, HEED, and PEGASIS. LEACH is the first protocol to use hierarchical routing to increase network lifetime. It forms clusters with local heads that collect data from members and transmit to the base station. HEED uses residual energy and network topology features to select distributed cluster heads. PEGASIS forms chains between sensors so each transmits to a close neighbor, avoiding hotspots. The document analyzes these algorithms and compares their effects on network lifetime.
The document presents an overview of QoS aware routing protocols for wireless sensor networks. It discusses the EQRS protocol which uses a link cost function and path discovery phase to establish multiple paths between nodes while considering energy efficiency and QoS metrics. It also briefly describes the SAR and DAST protocols, with SAR using a table-driven approach to create multiple paths from sensors to a sink node based on energy resources and packet priority, and DAST utilizing location information and remaining energy to select paths.
This document discusses power aware routing protocols for wireless sensor networks. It begins by describing wireless sensor networks and how they are used to monitor environmental conditions. It then classifies routing protocols for sensor networks based on their functioning, node participation style, and network structure. Specific examples are provided for different types of routing protocols, including LEACH, TEEN, APTEEN, SPIN, Rumor Routing, and PEGASIS. Chain-based and clustering routing protocols are also summarized.
This document discusses network topologies, switching, and routing algorithms. It defines different network topologies including mesh, star, bus, ring, tree, and hybrid topologies. It also describes hubs, switches, circuit switching, message switching, packet switching, datagram networks, and virtual circuit networks. For routing algorithms, it explains distance vector routing which uses hop count as the routing metric and link state routing which uses weighted metrics to calculate the shortest path.
Wireless LANs can be used for several applications, including extending a wired LAN to cover open or remote areas, connecting nearby buildings, providing mobile access to laptop users, and enabling temporary ad hoc networks. Wireless LANs use either infrared or radio frequency transmission and can be configured in various network topologies like peer-to-peer or with a central hub device. While infrared avoids licensing, it has limitations on range and ambient light interference, while radio frequency options operate in either licensed narrowband microwave spectra or unlicensed industrial, scientific and medical bands.
This document summarizes several energy-aware routing protocols for wireless sensor networks. It discusses classical approaches like flooding and gossiping and their deficiencies. It then describes the SPIN protocol which uses negotiations and metadata to adapt to resource constraints. Directed Diffusion is also covered, using interests, data messages, gradients, and reinforcement to set up multiple paths between sources and sinks. The document provides details on how these protocols establish and maintain paths while conserving energy in wireless sensor networks.
The document discusses routing protocols in wireless sensor networks. It outlines several key challenges for routing protocols including node deployment, network dynamics, energy conservation, fault tolerance, scalability, and hardware constraints. It then describes several common routing techniques used in wireless sensor networks, including proactive, reactive, and hybrid path establishment approaches, as well as flat, hierarchical, and location-based network structures. Finally, it discusses different protocol operations such as multipath routing, query-based routing, negotiation-based routing, and supporting quality of service metrics.
EC8702 adhoc and wireless sensor networks iv eceGOWTHAMMS6
This document outlines the syllabus for a course on Adhoc and Wireless Sensor Networks. It covers five units: (1) Introduction to Adhoc Networks and routing protocols, (2) Introduction to sensor networks and architectures, (3) Networking concepts and protocols for sensor networks, (4) Security issues in sensor networks, and (5) Sensor network platforms and tools. Some key topics discussed include characteristics of adhoc networks, challenges in routing, components and applications of wireless sensor networks, and medium access schemes. The objectives are for students to learn the fundamentals and apply their knowledge to identify suitable protocols based on network requirements and understand security and transport layer issues in these networks.
This document discusses ad hoc and wireless sensor networks. It describes several applications of ad hoc networks including military operations, collaborative work, emergency response, and wireless mesh networks. It also discusses wireless sensor networks and their use in fields like healthcare, environmental monitoring, and more. Finally, it outlines some of the major challenges in designing routing protocols for ad hoc networks such as mobility, bandwidth constraints, and resource limitations.
The document discusses secure routing protocols for wireless sensor networks. It begins by describing the components and design challenges of wireless sensor networks, including limited resources and security issues. It then discusses various attacks on wireless sensor networks like spoofing, selective forwarding, and sinkhole attacks. The document analyzes several secure routing protocols that aim to prevent such attacks, including Distributed Security Framework, Multipath Data Transfer Protocol, Secure and Energy Efficient Disjoint Route, and Bio-inspired Self-Organized Secure Autonomous Routing Protocol. It concludes by discussing future work to develop a new routing approach with low energy consumption, high delivery ratio, and strong security against possible threats.
This document discusses wireless sensor networks and sensor node technology. It provides details on the basic components and functionality of wireless sensor nodes, including hardware components like sensors, processing units, and communication units. It also describes software subsystems like operating systems, sensor drivers, and data processing applications. The document outlines design constraints for wireless sensor networks and trends toward miniaturization and integration. It summarizes research efforts to develop new sensor technologies, arrayed sensor networks, and techniques for interpreting sensor data for decision-making.
This document summarizes various techniques for saving energy in wireless sensor networks. It discusses how sensor nodes consume power through transmission, reception, processing and idle listening. It then describes approaches like sleep-wake scheduling, MAC protocols like S-MAC and T-MAC, in-network processing, network coding and scheduled/contention-based communication protocols to minimize energy usage. The goal is to reduce unnecessary listening and maximize the time sensors spend in sleep mode to improve battery life for sensor network applications.
The document discusses the syllabus for the course EC8702 Adhoc and Wireless Sensor Networks. The syllabus covers topics like adhoc network routing protocols, sensor network architecture and design issues, transport layer and security protocols for adhoc and sensor networks, and programming platforms and tools. The course objectives are to learn the fundamentals of adhoc and sensor networks, apply routing algorithms, identify physical and MAC layer protocols, and describe transport layer and security issues. Upon completing the course, students will be able to explain adhoc and sensor network basics, apply routing algorithms, identify protocols, describe transport and security issues, and program sensor nodes.
A General Self Organized Tree Based Energy Balance Routing Protocol for WSN Sathish Silence
GSTEB is a self-organized tree-based energy-balance routing protocol for wireless sensor networks. It aims to prolong network lifetime by balancing energy consumption across nodes. In GSTEB, the base station selects a root node and broadcasts its ID. Then each node selects its parent in a way that minimizes its distance to the root while balancing energy levels. The network operates in rounds, where a routing tree is constructed and nodes transmit sensed data to the base station along the tree. GSTEB dynamically changes the root node between rounds to further balance energy usage among all nodes. Simulation results show GSTEB outperforms other protocols in balancing energy consumption and extending network lifetime.
Seismic sensors and networks in Hawaii monitor earthquakes and volcanoes on the Big Island. The USGS operates several types of seismic stations, including short period and broadband sensors. Other groups also operate stations, and data is shared. The network helps track earthquake activity and volcanic processes. Hawaii experiences large earthquakes that can cause tsunamis, making seismic monitoring important for hazards assessment and early warning. Efforts aim to expand the network and coordination to improve earthquake reporting and monitoring statewide.
This document discusses the potential applications of embedded networked sensing systems. It outlines several motivating applications including monitoring seismic structure response, tracking contaminant transport, and monitoring ecosystems and biocomplexity. For each application, it describes the relevant science goals and how embedded networked sensing could provide data to advance understanding. It also discusses some of the research challenges for these applications and outlines initial steps being taken. The document concludes by discussing enabling technologies for embedded networked sensing systems.
The document summarizes research on using MEMS (Micro-Electro-Mechanical Systems) technology for seismology applications. It provides an overview of MEMS, discusses MEMS accelerometers and their commercial availability. It also describes the noise and detection requirements for seismology and current R&D efforts funded by DOE to develop low-noise MEMS seismometers, including projects using inductive, optical, and fluidic sensing techniques with proof masses up to 2 grams.
This document discusses various seismic methods and concepts. It begins by defining the critical angle and Snell's law for refraction seismology. It then distinguishes between the reflection and refraction seismic methods. The refraction method involves keeping the source fixed while spacing receivers further from the source, resulting in an x-t plot. Various seismic arrivals are described like direct waves, reflections, and refractions. Factors that affect seismic waves like attenuation and energy partitioning are also summarized. The document concludes by covering seismic sources, instruments, and refraction seismic methods.
This document provides a short overview of the RAYFRACT seismic refraction data interpretation software. It lists the main functions of the software such as creating new profiles, importing seismic data, reviewing first breaks, smoothing inversions, automatic and manual refractor mapping, wavefront modeling, automatic picking, and ASCII data import. More detailed instructions are available in the software manual and PDF help files on the company's website.
Seismic sensors and networks in Hawaii monitor earthquakes and volcanoes on the Big Island. The USGS operates several types of seismic stations, including short period and broadband sensors. Other groups also operate stations, and data is shared. The network helps track earthquake activity and volcanic processes like movement of magma. Hawaii experiences large, damaging quakes due to active faults and volcanism. Better seismic coverage could help provide faster warnings for events and tsunamis, and protect infrastructure like the Mauna Kea observatories. The USGS works to modernize statewide monitoring through the ANSS program.
The document discusses seismic data networks, instruments, and data centers. It describes the different types of seismic networks including global, regional, local, temporary, and seismic arrays. It also discusses several major seismic data centers such as NEIC, ORFEUS, IRIS, ISC, GEOFON, EMSC, and EarthScope. Finally, it covers various seismic observables including translations measured as displacement, velocity, and acceleration. It also discusses strain, rotations, and the ranges of measurements for different seismic phenomena.
Wireless sensor networks consist of small, low-cost sensors that can monitor various environmental conditions. Each sensor node contains components like a CPU, memory, analog-to-digital converters, sensors, and a radio transceiver. Sensor networks have a wide range of applications in areas like environmental monitoring, healthcare, agriculture, and infrastructure management. However, designing efficient sensor networks presents many challenges related to limited energy, scalability, heterogeneity, self-configuration, and security.
Single node architecture: hardware and software components of a sensor node - WSN
Network architecture: typical network architectures-data relaying and aggregation strategies -
MAC layer protocols: self-organizing, Hybrid TDMA/FDMA and CSMA based MAC- IEEE
802.15.4
This document discusses ad-hoc and mobile ad-hoc networks (MANETs). It defines an ad-hoc network as a wireless local area network where devices are part of the network only during communication sessions. A MANET is defined as a self-configuring network of mobile routers connected by wireless links. The document outlines the network architecture of MANETs and discusses applications, characteristics, requirements, and challenges of routing in these networks. It describes different types of routing protocols for MANETs including proactive, reactive, table-driven, and hybrid protocols.
The document provides information about ad-hoc networks, including their characteristics, applications, design issues, and routing protocols. Some key points:
- Ad-hoc networks are infrastructure-less and use multi-hop wireless links between mobile nodes, requiring distributed routing protocols. They are suitable for situations requiring quick deployment like emergencies or military operations.
- Challenges for routing in ad-hoc networks include the dynamic topology, limited bandwidth and energy of nodes, and lack of a centralized entity. Traditional link-state and distance-vector routing protocols are examined.
- Popular link-state protocols like OSPF work by flooding link-state information to build a shared topology database and calculate the shortest path tree
This document discusses ad-hoc wireless networks and provides examples of different types including sensor networks and vehicular networks. It summarizes key challenges in routing for ad-hoc networks due to lack of infrastructure, mobility, and limited bandwidth. Specific routing protocols for ad-hoc networks like DSR are described, focusing on on-demand route discovery and maintenance. Considerations for sensor networks include power efficiency through data aggregation and computation instead of communication. Vehicular networks introduce extreme mobility that makes traditional routing difficult.
This document provides an overview of various medium access control (MAC) protocols for wireless sensor networks. It discusses distributed and centralized MAC protocols, including DFWMAC, EY-NPMA, ISMA, RAP, RAMA, Zhang's and Acampora's proposals, and DTMP. It also covers hybrid access protocols like RRA, PRMA, RRA-ISA, DQRUMA, and MASCARA. Additionally, it summarizes MAC protocols like S-MAC, T-MAC, B-MAC, P-MAC, Y-MAC, and Z-MAC and discusses their key characteristics and performance results.
A wireless sensor network (WSN) consists of spatially distributed sensor nodes that monitor environmental or physical conditions cooperatively. Key features of WSNs include large numbers of low-cost nodes with strict energy constraints, short-range wireless connections, and data-centric routing where data is aggregated and fused as it travels towards base stations. WSNs require specialized protocols for tasks like media access control, data dissemination, and energy-efficient operation. WSNs have applications in environmental monitoring, medical care, military operations, and more.
Wireless sensor networks consist of distributed sensors that monitor conditions like temperature and sound and transmit data to a central location. They have two types - structured networks which are pre-planned and unstructured which are randomly deployed. The document reviews issues in wireless sensor networks like energy constraints and quality of service. It also discusses network services, internal sensor systems, applications, and communication protocols. Open research areas are identified in localization, coverage, security, cross-layer optimization and mobility support to improve energy efficiency and performance.
This document discusses data communication networks and the ISO-OSI reference model. It begins with an overview of the basic components of a communication network including sources that generate data, transmitters that convert data to signals, transmission systems that carry the data, receivers that convert signals back to data, and destinations that receive the data. It then discusses networking concepts like point-to-point vs. networked communication and examples of wide area networks and local area networks. The document also introduces the seven-layer ISO-OSI reference model and provides examples of the functions of the physical, data link, network, and transport layers. It concludes with a diagram summarizing the key functions of each layer.
This ppt is brief description about basic concepts of data communication network.this slide shows description about network topologies,network configuration and layers in osi model.
Wireless sensor networks are composed of small, low-cost sensor nodes that are densely deployed to monitor environmental conditions. Each node has sensing, processing and communication capabilities. Sensor networks have many applications including military surveillance, environmental monitoring, health monitoring, smart homes/offices, and inventory management. Routing data efficiently in sensor networks faces challenges due to the large number of nodes, limited energy/resources of nodes, and dynamic network topology changes. Common routing architectures include layered architectures where nodes are organized in layers based on distance from the base station, and clustered architectures where nodes are organized into clusters with cluster heads routing data.
Networks connect computers and devices to enable sharing of resources and communication between users. They come in various topologies like bus, star, ring and hybrid and use different media like coaxial cable, twisted pair, fiber optic or wireless. Common networking technologies include Ethernet, Token Ring, WiFi and FDDI, each with their own standards and characteristics. Understanding networks involves knowledge of topologies, media, technologies and how they work together to transmit and receive signals that represent digital data.
This document discusses energy-efficient sensor networks. It defines sensor networks and sensor nodes, which consist of sensing, processing, and communication devices. Common sensor node applications include environmental monitoring, structural health monitoring, medical diagnostics, and more. The document outlines challenges for sensor nodes related to limited resources and need for energy efficiency. It then discusses various techniques for conserving energy at the MAC layer and network layer, including efficient routing protocols like Directed Diffusion, LEACH, and GEAR.
This document discusses local area networks (LANs) and their applications, architectures, and technologies. It covers:
1) Common LAN applications like personal computer networks, back-end networks, storage area networks, and high-speed office networks.
2) Key aspects of LAN architecture including topology (e.g. bus, star, ring), transmission medium, IEEE 802 standards, and the functions of bridges and switches.
3) Protocol architectures with descriptions of the physical, logical link control, and media access control layers, as well as common frame formats.
Wireless LANs allow for wireless transmission of data within a local area network (LAN). The document discusses:
1. Wireless LANs were initially more expensive and had lower data rates than wired LANs, but these issues have been addressed and wireless LAN popularity has grown.
2. Wireless LANs are commonly used to extend existing wired LANs by avoiding cable installation, and to provide connectivity in areas not suited for wired LANs like large open spaces.
3. The IEEE 802.11 standard defines the media access control (MAC) and physical layers for wireless LANs. It uses carrier sense multiple access with collision avoidance (CSMA/CA) for distributed
Wireless sensor networks use large numbers of small, low-cost sensors that communicate wirelessly to monitor conditions like temperature, sound, pollution levels, pressure, etc. Sensors collect data and pass it to a base station, which can be accessed through the internet. Wireless sensor networks can be used for applications like environmental monitoring, smart grids, healthcare, agriculture, and more. They face challenges related to power efficiency, security, scalability and operating in different environments.
This document discusses communication networks and provides details about various types of networks:
- It classifies networks according to how information flows, including switching networks and broadcast networks. It describes circuit switching and packet switching in switching networks.
- It discusses different types of networks based on coverage area, including local area networks (LANs), metropolitan area networks (MANs), and wide area networks (WANs). It provides examples for each type.
- It describes the Open Systems Interconnection (OSI) reference model and its seven layers, using the link layer as an example to explain protocols.
fundamental of networking course, LAN,WAN,TCP,IPHusseinAwil
This document provides an overview of network fundamentals including network structure, protocols, transmission media, and hardware. It discusses the basic concepts of communications and networking. It describes common network transmission media like coaxial cable, twisted pair, optical fiber, and wireless transmission. It also explains key network hardware like hubs, bridges, routers, switches, and various wide area network technologies. Finally, it distinguishes between local area networks and wide area networks.
This document presents an overview of wireless sensor networks. It discusses the architecture, which includes sensor nodes, gateways, and a base station. It also covers routing protocols, applications like environmental monitoring, and network topologies. Finally, it describes different types of sensors used in wireless sensor networks like mechanical, optical, magnetic, and thermal sensors. The document concludes that wireless sensor networks can bridge the physical and digital worlds by establishing a nervous system for physical monitoring and data collection.
This document provides a short overview of the RAYFRACT seismic refraction data interpretation software. It lists the main functions of the software such as creating new profiles, importing seismic data, reviewing first breaks, smoothing inversions, automatic and manual refractor mapping, wavefront modeling, automatic picking, and ASCII data import. More detailed instructions are available in the software manual and PDF help files on the company's website.
This document provides an overview of wireless sensor networks. It discusses what sensor networks are and their applications in areas like military, industry, science and more. It describes the constraints of sensor networks like limited battery power, storage and processing. It outlines several research challenges in areas like medium access control, routing, time synchronization and localization. The document discusses different aspects of designing sensor network protocols and architectures to address issues of energy efficiency, scalability, heterogeneity and self-configuration.
This document discusses the potential applications of embedded networked sensing systems. It outlines three main applications: 1) seismic structure monitoring to better understand building and soil responses, 2) contaminant transport monitoring to track contaminant movement, and 3) ecosystem monitoring to study wildlife populations over time. The document also discusses enabling technologies, challenges, and a taxonomy for classifying different embedded sensing systems.
The document summarizes research on using MEMS (Micro-Electro-Mechanical Systems) technology for seismology applications. It provides an overview of MEMS, discusses MEMS accelerometers and their commercial availability. It also covers noise and detection theory, current R&D efforts funded by DOE to develop low-noise MEMS seismometers, and the outlook for using MEMS in seismology. Key challenges include achieving large proof masses, weak springs, and low noise at low frequencies needed for weak motion seismology.
The document discusses seismic data networks, instruments, and data centers. It describes the different types of seismic networks including global, regional, local, temporary, and seismic arrays. It also discusses several major seismic data centers such as NEIC, ORFEUS, IRIS, ISC, GEOFON, EMSC, and EarthScope. Finally, it covers various seismic observables including translations (displacement, velocity, acceleration), strain, and rotations that seismometers are capable of measuring.
The document describes a wireless GPS wristwatch tracking solution called TIDGET. TIDGET is a low power GPS tracking device developed by NAVSYS for the US Army. It uses a client/server approach to send raw GPS data through a ZigBee wireless link to a LocatorNet server for processing. The server uses software defined radio to compute positions from the GPS data. TIDGET can operate for over 30 days on a wristwatch battery by offloading GPS processing to the server. A web portal allows users to access location data from the tracking devices.
This document provides a tutorial about a seismic sensor network. It discusses:
1) The special demands of seismic and acoustic applications including large-scale deployment, challenged networks, and remote monitoring requirements.
2) An overview of the software and hardware used in the network including the CDCCs, Q330 data loggers, Duiker data collection software, and DTS remote management software.
3) How to assemble a seismic node in 30 minutes by connecting sensors, data loggers, and wireless nodes together and reprogramming the nodes.
The HP MEMS sensor demonstrates potential for use in seismic imaging applications by providing a flat frequency response down to DC and low noise floor of less than 10 ng/√Hz. Testing at the USGS confirmed noise levels matching the lowest levels on Earth and matching signals down to 25 mHz compared to a reference sensor. A custom ASIC integrated circuit is being developed to enable low power sensors for dense wireless arrays to further improve seismic image resolution.
This document provides an overview of seismic waves:
1) It describes the three main types of seismic waves - P waves, S waves, and surface waves - and how they propagate through the Earth.
2) Key concepts discussed include body waves that travel through the Earth's interior and surface waves that travel along the Earth's surface.
3) The document also discusses seismic wave properties like velocity, period, wavelength, and attenuation as they travel through different Earth layers and are affected by geological structures.
The document discusses various sensor technologies and considerations for sensing systems. It covers topics such as phase linearity, transducer terminology, sensor categorization based on physical phenomena and measuring mechanism, specifications of sensors including accuracy and resolution, strain gauges, acceleration sensing, force sensing, displacement sensing, velocity sensing, shock sensing, angular motion sensing, MEMS technology, and considerations for designing sensing systems. The key aspects covered are the operating principles, advantages, and limitations of different sensor types.
This document provides an overview of seismic waves:
1) It describes the three main types of seismic waves - P waves, S waves, and surface waves - and how they propagate through the Earth.
2) Key concepts discussed include body waves that travel through the Earth's interior and surface waves that travel along the Earth's surface.
3) The document also discusses seismic wave properties like velocity, period, wavelength, and attenuation as they travel through different Earth layers and are affected by subsurface structures.
An illumination is a decorative embellishment added to handwritten manuscripts before the invention of the printing press. It enhances pages with gold leaf, silver, or other colors. Illuminated letters were enlarged and colored at the start of paragraphs to draw attention. Images of animals, plants, or mythical creatures were sometimes incorporated into the letters. Monks and nuns created illuminated manuscripts in monasteries, adding illuminations to important documents by request of royalty or religious leaders to make them appear more significant. The tradition originated in ancient Egypt and continued for hundreds of years in medieval Europe. Creating illuminations required specialized roles of parchment maker, scribe, illuminator, and bookbinder working together. Illuminations highlighted a time when reading
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms.
This document discusses methods for calculating illumination levels in indoor spaces. It describes the lumen method, which uses calculations involving flux, illumination levels, room dimensions, and reflectance values to determine lighting requirements. It also covers utilization factors, maintenance factors, glare indices, and considerations for lighting layout and control of glare. The goal is to provide uniform illumination while avoiding discomfort glare through analytical lighting design methods.
This document summarizes a lecture on power system protection and transient stability. It discusses radial and networked power system protection schemes, including inverse-time overcurrent relays, directional relays, impedance relays, and differential relays. It also covers sequence of events recording, fault location using GPS, and an overview of power system transient stability.
This document provides information on advanced lighting controls and mandatory control requirements for lighting systems. It discusses why lighting control is important, including user needs, legal codes, and energy efficiency. The document outlines mandatory control requirements from energy codes, including automatic shutoff controls, space controls, and occupancy sensor requirements. It also discusses control requirements for exterior lighting, additional controls for special applications, and considerations for green building projects. The document provides an overview of passive and active lighting control strategies and examples of sensor specifications and room layout diagrams.
Instrument to measure the bidirectional reflectanceajsatienza
This instrument measures the bidirectional reflectance distribution function (BRDF) of surfaces with the following properties:
1. It measures the BRDF for eight illumination angles from 0 to 65 degrees, three colors (475, 570, 658 nm), and over 100 selected viewing angles.
2. The viewing zenith angles range from 5 to 65 degrees, and the azimuth angles range from 0 to ±180 degrees relative to the illumination direction.
3. Tests show it can measure the BRDF of flat surfaces with a precision of 1-5% and an accuracy of 10% of the measured reflectance.
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
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Throughout his career, he has taken on multifaceted roles, from leading technical project management teams to owning solutions that drive operational excellence. His conscientious and proactive approach is unwavering, whether he is working independently or collaboratively within a team. His ability to connect with colleagues on a personal level underscores his commitment to fostering a harmonious and productive workplace environment.
Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
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How to Add Chatter in the odoo 17 ERP ModuleCeline George
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
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Assessment and Planning in Educational technology.pptxKavitha Krishnan
In an education system, it is understood that assessment is only for the students, but on the other hand, the Assessment of teachers is also an important aspect of the education system that ensures teachers are providing high-quality instruction to students. The assessment process can be used to provide feedback and support for professional development, to inform decisions about teacher retention or promotion, or to evaluate teacher effectiveness for accountability purposes.
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How to Build a Module in Odoo 17 Using the Scaffold MethodCeline George
Odoo provides an option for creating a module by using a single line command. By using this command the user can make a whole structure of a module. It is very easy for a beginner to make a module. There is no need to make each file manually. This slide will show how to create a module using the scaffold method.
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Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
By Dr. Vinod Kumar Kanvaria
Main Java[All of the Base Concepts}.docxadhitya5119
This is part 1 of my Java Learning Journey. This Contains Custom methods, classes, constructors, packages, multithreading , try- catch block, finally block and more.
2. Overview
• What is a sensor network?
– Sensing
– Microsensors
– Constraints, Problems, and Design Goals
• Overview of Research Issues and
Challenges
8. Objective
• Large-scale, fine-grained,
heterogeneous sensing
– 100s to 1000s of nodes providing high
resolution
– Spaced a few feet to 10s of meters apart
– In-situ sensing
– Hetegerogeneous sensors
9. Properties
• Wireless
– Easy to deploy: ad hoc deployment
– Most power-consuming: transmiting 1 bit ≈ executing 1000
instructions
• Distributed, multi-hop
– Closer to phenomena
– Improved opportunity for LOS
– radio signal is proportional to 1/r4
– Centralized apporach do not scale
– Spatial multiplexing
• Collaborative
– Each sensor has a limited view in terms of location and sensor type
– Sensors are battery powered
– In-network processing to reduce power consumption and data
redundancy
10. Basic Terminology and
Concepts
• Phenomenon: the physical entity being
monitored
• Sink or base station: a collection point to
which the sensor data is disseminated
– Relatively resource rich node
• Sensor network periodically samples
phenomena in space and time
• Sink floods a query
12. Other variations
• Sensors mobile or not?
• Phenomena discrete or continuous?
• Monitoring in real-time or for replay
analysis?
• Ad hoc queries vs. long-running queries
15. Protocol Stack: Physical Layer
• Frequency selection
• Carrier frequency generation
• Signal detection
• Modulation
• Not the focus of this class
– We will focus on the link layer and above
16. Protocol Stack: Physical Layer
• Issues
– Hardware cost
• How do we get down to $1/node?
– Radio
• Ultrawideband?
– Very low powered, short pulse radio spread
over several GHz
– 40Mbps ~ 600Mbps
17. Protocol Stack: Physical Layer
• Radio (Cont.)
– Zigbee/IEEE 802.15.4
• 2.4GHz radio band (= 802.11.b & Bluetooth)
• 250Kbps
• Up to 30 meters
– Pico radio
• 100Kbps
• Limit power consumption to 100 uW
– Other? (infra red, passive elements …)
18. Protocol Stack: Data Link
Layer
• Multiplexing of data streams
• Data frame detection
• Medium access
• Error control
19. Data Link Layer
• Goals:
– Creation of the network infrastructure
– Fair and efficient sharing of of communication resources
between sensor nodes
• Existing solutions?
– Cellular: single hop network is impractical for sensor
networks
– Ad hoc MACs, e.g., 802.11 or Bluetooth: Power consuming
– Scale
– Data centric operation
– Security
• WEP for 802.11 is broken
20. Data Link Layer: Medium
Access Control
• Basic strategy: turn off radio
transceiver as much as possible, while
receiving and transmitting data
• Techniques: TDMA, application-layer
transmission scheduling, SMAC, ZMAC,
BMAC, ...
21. Protocol Stack: Network
Layer
• Design principles
– Power efficiency
– Data-centric
– Data aggregation when desired and possible
– Attribute-based addressing and location
awareness: no IP address
22. Minimum Energy Routing
• Maximum
power abailable
route
• Minimum
energy route
• Minimum hop
(MH) route
23. Directed Diffusion
• Route based on
attributes and
interests
• To be covered
later in the
semester
25. Transport Layer
• End-to-end Reliability
– Multi-hop retransmission: worth it?
– Congestion: relatively little related work
• End-to-end security
– Like SSL: authentication, encryption, data
integrity
– Good? What about data aggregation?
27. Other Important Issues
• Operating system
– TinyOS
– MANTIS OS
• Localization, Time Synchronization, and
Calibration
• Aggregation/Data Fusion
• Security
– Encryption
– Authentication
– Data integrity
– Availability: DOS attacks
• Privacy
28. Time and Space Problems
• Timing synchronization
• Node Localization
• Sensor Coverage
29. Time Synchronization
• Time sync is critical at many layers in sensor nets
– Aggregation, localization, power control
Ref: based on slides by J. Elson
30. Sources of time
synchronization error
• Send time
– Kernel processing
– Context switches
– Transfer from host to NIC
• Access time
– Specific to MAC protocol
• E.g. in 802.11, sender must wait for CTS (Clear To Send)
• Propagation time
– Dominant factor in WANs
• Router-induced delays
– Very small in LANs
• Receive time
• Common denominator: non-determinism
31. Conventional Approaches
• GPS at every node (around 10ns accuracy)
– doesn’t work indoo
– cost, size, and energy issues
• NTP
– Primary time servers are synchronized via atomic clock
– Pre-defined server hierarchy
– Nodes synchronize with one of a pre-specified time servers
– Can support coarse-grain time synchronization
• Inefficient when fine-grain sync is required
– Sensor net applications, e.g., localization, beamforming, TDMA
– Discovery of time servers
– Potentially long and varying paths to time-servers
– Delay and jitter due to MAC and store-and-forward relaying
32. Localization
• Why each node should find its location?
– Data meaningless without context
– Geographical forwarding/addressing
• Why not just GPS at every node?
– Large size and expensive
– High power consumption
– Works only outdoors with LOS to satellites
– Overkill: Often only relative position is needed
33. What is Location?
• Absolute position on geoid
• Location relative to fixed beacons
• Location relative to a starting point
– e.g. inertial platforms
• Most applications:
– location relative to other people or objects,
whether moving or stationary, or the location
within a building or an area
34. Techniques for Localization
• Measure proximity to beacons
– Near a basestation in a room
• Active Badge for indoor localization
– Infrared basestations in every room
– Localizes to a room as room walls act as barriers
• Most commercial RF ID Tag systems
– Strategically located tag readers
– Beacon grid for outdoor localization
• Estrin’s system for outdoor sensor networks
– Grid of outdoor beaconing nodes with know position
– Position = centroid of nodes that can be heard
– Problem
• Not location sensing but proximity sensing
• Accuracy of location is a function of the density of
beacons
35. Localization
• Measure direction of landmarks
– Simple geometric relationships can be used to determine
the location by finding the intersections of the lines-of-
position
– e.g. Radiolocation based on angle of arrival (AoA)
• can be done using directional antennas or antenna
arrays
• need at least two measurements
BS
φ2
BS
φ1
MS
φ3
BS
36. Localization: Range-based
• Measure distance to beacons
– Measure signal-strength or time-of-flight
– Estimate distance via received signal strength
• Mathematical model that describes the path loss attenuation
with distance
• Use pre-measured signal strength contours around fixed
beacon nodes
– Distance via Time-of-arrival (ToA)
• Distance measured by the propagation delay
– Distance = time * c
• Active vs. passive
– Active: receiver sends a signal that is bounced back so that the
receiver know the round-trip time
– Passive: receiver and transmitter are separate
» time of signal transmission needs to be known
– N+1 BSs give N+1 distance measurements to locate in N
dimensions
38. Many other issues
• What about errors? Collisions? No
LOS?
• If sensors are mobile, when should we
localize?
• Multi-hop localization?
39. Sensor Network Coverage
GATEWAY
MAIN SERVER
CONTROL
CENTER
• The Problem:
– Given:
• Ad hoc sensor field with some number of nodes with known location
• Start and end positions of an agent
– Want:
• How well can the field be observed?
• Example usage
– Commander
• Weakest path: what path is the enemy likely to take?
– Network manager
• Weakest path: where to deploy additional nodes for optimum coverage?
– Soldier in the battlefield
• Strongest path: what path to take for maximum coverage by my command?
• Weakest path: how to walk through enemy sensor net or through minefield?
Ref: based on slides by Seapahn Megerian
40. Exposure Model of Sensors
• Likelihood of detection by sensors is a function of time
interval and distance from sensors.
• Minimal exposure paths is worst case scenarios in a
field:
Ref: based on slides by Seapahn Megerian
41. Other Issues
• Coverage for continuous phenomena
• Role: Sensor as a source of information
and as a router
– What if we route through a critical node
and drain its energy compromising future
coverage?
42. Data Management Problems
sensors • Observer interested in phenomena
with certain tolerance
– Accuracy, freshness, delay
• Sensors sample the phenomena
• Sensor Data Management
– Determining spatio-temporal
sampling schedule
observer
• Difficult to determine locally
– Data aggregation and fusion
phenomena
• Interaction with routing
– Network/Resource limitations
• Congestion management
• Load balancing
• QoS/Realtime scheduling
43. Spatio-Temporal Sampling
• How to express interests and translate into
actions
• How often should a given sensor report?
– Collected data should meet application goals at
reasonable load to the network
– Data/event driven
– Locally difficult to determine appropriate
sampling/reporting rate
– Collaboration needed to improve local estimate
44. Data Aggregation and Fusion
• Aggregate related data from multiple
sensors
– Reduce data size and overall load
– Provide more comprehensive estimate of
data importance to manage sensors better
• Support for effective data aggregation
– Routing and MAC support
– Sampling schedules should be coordinated
– Tradeoff between data quality and
resource demand should be exposed to the
application
45. Summary: Key Design Challenges
• Energy efficiency
– Sensor nodes should run for several years
without battery replacement
– Energy efficient protocols are required
– More efficient batteries
• But, efficient battery development is always
slower than processor/memory development
– Energy harvesting
46. Key Design Challenges
• Responsiveness
– Periodic sleep & wake-up can reduce the
responsiveness of sensors
• Important events could be missed
– In real-time applications, the latency
induced by sleep schedules should be kept
within bounds even when the network is
congested
47. Key Design Challenges
• Robustness
– Inexpensive sensors deployed in a harsh
physical environment could be unreliable
• Some sensor could be faulty or broken
– Global performance should not be sensitive
to individual sensor failures
– Graceful performance degradation when
there are faulty sensors
48. Key Design Challenges
• Synergy
– Moore’s law apply differently
• Sensors may not become more powerful in terms of
computation and communication capability
• Cost reduction is the key to a large number of sensor
deployment
– A WSN as a whole needs to be much more capable
than a simple sum of the capabilities of the
sensors
• Extract information rather than raw data
– Also support efficient collaborative use of
computation, communication, and storage resources
49. Key Design Challenges
• Scalability
– 10,000 or more nodes for fine-granularity
sensing & large coverage area
– Distributed, localized communication
– Utilize hierarchical structure
– Address fundamental problems first
• Failure handling
• In-situ reprogramming, e.g., Deluge
• Network throughput & capacity limits?
50. Key Design Challenges
• Heterogenity
– Heterogeneous sensing, computation, and
communication capabilities
– e.g., a small number of devices of higher
computational capabilities & a large number of low
capability nodes -> two-tier WSN architecture
– Best architecture exist for all application?
– How to determine a right combination of
heterogeneous devices for a given application?
51. Key Design Challenges
• Self-configuration
– WSNs are unattended distributed systems
– Nodes have to configure their own network
topology;
• Localize, synchronize & calibrate; and
• Coordinate communications for themselves
52. Key Design Challenges
• Self-optimization & adaptation
– WSNs cannot be optimized a priori
– Environment is unpredictble, and may
change drastically
– WSN protocols should be adaptive & adapt
themseleves online
53. Key Design Challenges
• Systematic design
– Tradeoff btwn two alternatives
• (1) Fine-tuning to exploit application specific
characteristics to improve performance
• (2) More flexible, easy-to-generalize design
approaches sacrificing some performance
– Systematic design methodologies for reuse,
modularity & run-time adaptation are
required
54. Key Design Challenges
• Security & Privacy
– Security support for critical applications,
e.g., battlefield monitoring
– Avoid sabotage in, e.g., structural
monitoring
– Support privacy of medical sensor data
– Severe resource limitations, but challenging
security & privacy issues