Introduction to IoT. Srikanth Saripalli Vinayak Naik

Transcription

1 Introduction to IoT Srikanth Saripalli Vinayak Naik

2 Sensor devices are becoming widely available - Programmable devices - Off-the-shelf gadgets/tools 2

3 More Things are being connected Home/daily-life devices Business and Public infrastructure Health-care 3

4 People Connecting to Things ECG sensor Internet Motion sensor Motion sensor Motion sensor 4

5 Things Connecting to Things - Complex and heterogeneous resources and networks 5

6 Industrial M2M

7 LoRa

8 Wireless Sensor Networks (WSN) End-user Gateway Core network e.g. Internet Sink node Gateway Computer services - The networks typically run Low Power Devices - Consist of one or more sensors, could be different type of sensors (or actuators) 8

9 How are the networks changing? Extensions More nodes, more connections, IPv6, 6LowPan,... Any TIME, Any PLACE + Any THING M2M, IoT Billions of interconnected devices, Everybody connected. Expansions Broadband Enhancements Smart networks Data-centric and content-oriented networking Context-aware (autonomous) systems 9

10 Future Networks

11 Thing connected to the internet Image Courtesy: : CISCO 11 11

12 Internet of Things (IoT) Extending the current Internet and providing connection, communication, and inter-networking between devices and physical objects, or "Things," is a growing trend that is often referred to as the Internet of Things. The technologies and solutions that enable integration of real world data and services into the current information networking technologies are often described under the umbrella term of the Internet of Things (IoT) 12

13 Why should I learn about IoT? Business trend Emerging technologies Growing IoT Services and Application Cyber Physical Systems (CPS) 13

14 Opportunities 14 Source:

15 Technology trend 15

16 Market growth According to a study conducted by Frost & Sullivan in 2011, the global RFID market of $3 billion to $4 billion (in 2009) will grow by twelve percent per year through 2016 and reach a volume of approximately $6.5 billion to almost $9 billion. 80 percent of all households in the European Union are expected to have intelligent power meters by A building s energy management can then be monitored and administered remotely via a smartphone or a PC. Market experts predict that this global market, which represented $5.3 billion in In February 2012, the Chinese government therefore decided to set up a fund of approximately $775 million to support this field in the next five years. It will grow to $11 billion by This sector is expected to grow to $116 billion by 2015, according to a report published by the Xinhua News Agency in late Source: Siemens, ts-and-forecasts-growth-market-of-the-future.html 16

17 Smart product sales Source: Siemens, ts-and-forecasts-growth-market-of-the-future.html 17

18 Internet Connected devices Source: Siemens, ts-and-forecasts-growth-market-of-the-future.html 18

19 Global Data Generation - Everyday around 20 quintillion (10^18) bytes of data are produced (Source: 01.ibm.com/software/data/bigdata/). - This data includes textual content (unstructured, semi-structured, structured) to multimedia content (images, video and audio), on a variety of platforms (enterprise, social media, and sensors). 19

20 Data Generation 20

21 Internet of Things Module Image courtesy: Wilgengebroed 21

22 Main Goals Overview of IoT and wireless sensor networks. What is Internet of Thing(s)? What are sensor networks? Unique characteristics/challenges, etc. State-of-the-art in IoT and sensor networks research. 1-22

23 Topics Introduction RF and Wireless Sensors Applications Estimation Routing and data dissemination Storage, querying, and aggregation Topology control Deployment issues Localization Time synchronization Medium access control Energy models 1-23

24 Introduction What are sensor networks and IoT? Unique characteristics/challenges. Basic concepts and terminology. 1-24

25 What are sensor networks? Networks of typically small, battery-powered, wireless devices. On-board processing, Communication, and Sensing capabilities. Sensors Storage Processor P O W E R Radio 1-25 device schematics

26 Components Sensors Storage Processor Radio WSN device schematics P O W E R Low-power processor Limited processing Memory Limited storage Radio Low-power Low data rate Limited range Sensors Scalar sensors: temperature, light, etc. Cameras, microphones Power 1-26

27 Why Now? Use of networked sensors dates back to the 1970s Primarily wired and Centralized Today, enabling technological advances in VLSI, MEMS, and wireless communications Ubiquitous computing and Ubiquitous communications 1-27

28 Vision: Embed the World Embed numerous sensing nodes to monitor and interact with physical world Network these devices so that they can execute more complex task Images from UCLA CENS 1-28

29 Examples of WSN Platforms PC-104+ (off-the-shelf) UCLA TAG (Girod) 1-29 UCB Mote (Pister/Culler)

30 Design Challenges Why are sensor network challenging/unique from a research point of view? Typically, severely energy constrained Limited energy sources (e.g., batteries) Trade-off between performance and lifetime Self-organizing and self-healing Remote deployments Scalable Arbitrarily large number of nodes 1-30

31 Design Challenges (Cont d) Heterogeneity Devices with varied capabilities Different sensor modalities Hierarchical deployments Adaptability Adjust to operating conditions and changes in application requirements Security and privacy Potentially sensitive information Hostile environments 1-31

32 Applications Monitoring Scientific and ecological applications Non-intrusiveness Real-time and high spatial-temporal resolution Remote and hard-to-access areas Surveillance and tracking Reconnaissance Perimeter control Smart Environments Agriculture Manufacturing/industrial processes 1-32

33 Overview A Wireless Sensor Network (WSN) consists of base stations and a number of wireless sensors (nodes)

34 Overview (Cont.) Wireless Sensor Node: Components

35 Overview (Cont.) Characteristics of Sensor Networks Requirements: small size, large number, tether-less, and low cost Constrained by energy, computation, and communication Small size implies small battery Low cost & energy implies low power CPU, radio with minimum bandwidth and range Ad-hoc deployment implies no maintenance or battery replacement To increase network lifetime, no raw data is transmitted

36 Overview (Cont.) Ad Hoc Wireless Networks Large number of self-organizing static or mobile nodes that are possibly randomly deployed Near(est)-neighbor communication Wireless connections Links are fragile, possibly asymmetric Connectivity depends on power levels and fading Interference is high for omnidirectional antennas Sensor Networks and Sensor-Actuator Networks are a prominent example

37 Overview (Cont.) Distinguishing Features Sensor Networks are ad hoc networks (wireless nodes that self-organize into an infrastructure-less network) BUT, in contrast to other ad-hoc networks: Sensing and data processing are essential These have many more nodes and are more densely deployed Hardware must be cheap; nodes are more prone to failures Operate under very strict energy constraints Nodes are typically static The communication scheme is many-to-one (data collected at a base station) rather than peer-to-peer

38 Overview (Cont.) Lifetime Nodes are battery-powered Nobody is going to change the batteries. So, each operation brings the node closer to death. "Lifetime is crucial! To save energy: Sleep as much as possible Acquire data only if indispensable Use data fusion and compression Transmit and receive only if necessary. Receiving is just as costly as sending.

39 Overview (Cont.) Scalability and Reliability self-configure and be robust to topology changes (e.g., death of a node) maintain connectivity: can the Base Station reach all nodes? ensure coverage: are we able to observe all phenomena of interest? Maintenance Reprogramming is the only practical kind of maintenance. It is highly desirable to reprogram wirelessly.

40 Overview (Cont.) Data Collection Centralized data collection puts extra burden on nodes close to the base station. Clever routing can alleviate that problem. Clustering: data from groups of nodes are fused before being transmitted, so that fewer transmissions are needed Often getting measurements from a particular area is more important than getting data from each node Security and authenticity should be guaranteed. However, the CPUs on the sensing nodes cannot handle fancy encryption schemes.

41 Overview (Cont.) Power Supply AA batteries power the vast majority of existing platforms. They dominate the node size. Alkaline batteries offer a high energy density at a cheap price. The discharge curve is far from flat, though. Lithium coin cells are more compact and boast a flat discharge curve. Rechargeable batteries: Who does the recharging? Solar cells are an option for some applications. Fuel cells may be an alternative in the future. Energy scavenging techniques are a hot research topic (mechanical, thermodynamical, and electromagnetic).

42 Overview (Cont.) Radio Commercially-available chips Available bands: 433 and 916MHz, 2.4GHz ISM bands Typical transmit power: 0dBm. Power control Sensitivity: as low as -110dBm Narrowband (FSK) or Spread Spectrum communication. DS-SS (e.g., ZigBee) or FH-SS (e.g., Bluetooth) Relatively low rates (<100 kbps) save power.

43 Overview (Cont.) CPU The Microcontroller Unit (MCU) is the primary choice for innode processing. Power consumption is the key metric in MCU selection. The MCU should be able to sleep whenever possible, like the radio. Memory requirements depend on the application ATmega128L and MSP430 are popular choices

44 Overview (Cont.) Sensors The power efficiency of the sensors is also crucial, as well as their duty cycle MEMS techniques allow miniaturization

45 Environment monitoring (1) Great Duck Island 150 sensing nodes deployed throughout the island relay data temperature, pressure, and humidity to a central device. Data was made available on the Internet through a satellite link.

46 Environment monitoring (2) Zebranet: a WSN to study the behavior of zebras Special GPS-equipped collars were attached to zebras Data exchanged with peer-to-peer info swaps Coming across a few zebras gives access to the data

47 Medical application Vital sign monitoring Accident recognition Monitoring the elderly Intel deployed a 130-node network to monitor the activity of residents in an elder care facility. Patient data is acquired with wearable sensing nodes (the watch )

48 Data-dissemination Schemes Conventional Methods Direct communication with the base station Sensor nodes communicate with the base station directly. Energy consuming. Multi-hop Scheme Transmit through some other intermediate nodes. Energy consuming.

49 Data-dissemination Schemes (Cont.) Clustering Hierarchy