Internet of Things (CS-803 (C)) Unit 1 Notes

How unit 1 is examined

This unit covers what IoT is, its architecture, M2M and WoT, network parts and microcontrollers; the marks sit on logical design of IoT and IoT vs M2M.

IoT definition

<span style="display:inline-block;padding:.16em .6em;border:1.5px solid currentColor;border-radius:999px;font-size:.68em;font-weight:700;letter-spacing:.06em;text-transform:uppercase;opacity:.75">Not asked since 2022</span>

Definition. <mark>The Internet of Things is a network of physical objects embedded with sensors, software and connectivity that collect and exchange data over the Internet with little or no human intervention.</mark>

Key points.

A "thing" is any physical object with a unique identity, such as a thermostat, a car or a heart monitor.
Each thing senses its surroundings, sends the data over a network, and can be monitored or controlled remotely.
The aim is to turn raw data into decisions and automatic actions.

Characteristics

Definition. The characteristics are the properties that separate an IoT system from an ordinary network of computers.

Key points.

Connectivity: every thing can reach the network and other things.
Intelligence: sensing and data analysis let the system decide and act by itself.
Dynamic and self-adapting: devices change state, location and context, and the system adapts.
Heterogeneity: devices differ in hardware, protocols and networks, yet must interoperate.
Scale and security: billions of devices generate huge data, so identity, privacy and security are essential.

IoT conceptual and architectural framework

Definition. The framework is a layered view of IoT in which data flows from things upward to applications and commands flow back down.

Key points.

The perception (device) layer holds sensors and actuators that capture data and act.
The network layer carries the data through gateways, LAN and WAN to the Internet.
The processing (middleware) layer stores and analyses data, usually in the cloud.
The application layer delivers services such as smart home or smart farming to the user.

Components of IoT ecosystems

Definition. An IoT ecosystem is the set of parts that together sense, communicate, process and present data.

Key points.

Sensors and actuators are the devices that read the physical world and act on it.
Connectivity (Wi-Fi, Bluetooth, ZigBee, cellular) moves data via a gateway to the cloud.
The cloud or data platform stores, processes and analyses the data.
Applications and user interfaces (dashboards, mobile apps) show results and send commands.
Security and standards run across all parts.

Physical and logical design of IoT

Definition. Physical design describes the things, protocols and connectivity that make up IoT; <mark>logical design is the abstract description of IoT in terms of functional blocks, communication models and communication APIs, without technical detail.</mark>

Diagram. <figure class="ds-fig" style="margin:1.4rem 0;overflow-x:auto"><svg xmlns="http://www.w3.org/2000/svg" id="dsfig-u1-01" viewBox="0 0 1499 194" width="1499" height="194" role="img" aria-label="Logical design of IoT"><style>#dsfig-u1-01 .e{stroke:#454C5A;stroke-width:1.4;fill:none}#dsfig-u1-01 .e.hi{stroke:#2340B8;stroke-width:2.6}#dsfig-u1-01 .n{fill:#FFFFFF;stroke:#16181D;stroke-width:1.4}#dsfig-u1-01 .n.hi{fill:#E3E9FC;stroke:#2340B8;stroke-width:2.2}#dsfig-u1-01 .n.rb-b{fill:#16181D;stroke:#16181D}#dsfig-u1-01 .n.rb-r{fill:#BD3227;stroke:#BD3227}#dsfig-u1-01 text{font-family:"JetBrains Mono",ui-monospace,Menlo,Consolas,monospace;font-size:13px}#dsfig-u1-01 .t{fill:#16181D;font-weight:500}#dsfig-u1-01 .t.inv{fill:#FFFFFF;font-weight:700}#dsfig-u1-01 .kd{stroke:#16181D;stroke-width:1.2}#dsfig-u1-01 .dot{fill:#16181D}#dsfig-u1-01 .ann{fill:#2340B8;font-size:11px;font-weight:700}#dsfig-u1-01 .lbl{fill:#6F7787;font-family:system-ui,-apple-system,sans-serif;font-size:12px;font-weight:700}#dsfig-u1-01 .ptr{fill:#2340B8;font-size:12px;font-weight:700}#dsfig-u1-01 .ah{fill:#454C5A}#dsfig-u1-01 .ah.hi{fill:#2340B8}#dsfig-u1-01 .wl rect{fill:#FFFFFF;stroke:#DCE0E7}#dsfig-u1-01 .wl .t{font-size:12px;font-weight:700}#dsfig-u1-01 .wl.hi rect{fill:#2340B8;stroke:#2340B8}#dsfig-u1-01 .wl.hi .t{fill:#FFFFFF}html.dark #dsfig-u1-01 .e{stroke:#B1B7C3}html.dark #dsfig-u1-01 .e.hi{stroke:#8FA3FF}html.dark #dsfig-u1-01 .n{fill:#161920;stroke:#E6E8ED}html.dark #dsfig-u1-01 .n.hi{fill:#1E2748;stroke:#8FA3FF}html.dark #dsfig-u1-01 .n.rb-b{fill:#E6E8ED;stroke:#E6E8ED}html.dark #dsfig-u1-01 .n.rb-r{fill:#FF7E71;stroke:#FF7E71}html.dark #dsfig-u1-01 .t{fill:#E6E8ED}html.dark #dsfig-u1-01 .t.inv{fill:#0F1115}html.dark #dsfig-u1-01 .kd{stroke:#E6E8ED}html.dark #dsfig-u1-01 .dot{fill:#E6E8ED}html.dark #dsfig-u1-01 .ann{fill:#8FA3FF}html.dark #dsfig-u1-01 .lbl{fill:#858D9C}html.dark #dsfig-u1-01 .ptr{fill:#8FA3FF}html.dark #dsfig-u1-01 .ah{fill:#B1B7C3}html.dark #dsfig-u1-01 .ah.hi{fill:#8FA3FF}html.dark #dsfig-u1-01 .wl rect{fill:#161920;stroke:#2A2E37}html.dark #dsfig-u1-01 .wl.hi rect{fill:#8FA3FF;stroke:#8FA3FF}html.dark #dsfig-u1-01 .wl.hi .t{fill:#0F1115}</style><defs><marker id="ah1" viewBox="0 0 10 10" refX="9" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path class="ah" d="M0,1 L9,5 L0,9 z"/></marker><marker id="ahh1" viewBox="0 0 10 10" refX="9" refY="5" markerWidth="7" markerHeight="7" orient="auto-start-reverse"><path class="ah hi" d="M0,1 L9,5 L0,9 z"/></marker></defs><line class="e" x1="869" y1="37" x2="367.3" y2="101"/><line class="e" x1="869" y1="37" x2="1004.3" y2="101"/><line class="e" x1="869" y1="37" x2="1370.8" y2="101"/><line class="e" x1="367.3" y1="101" x2="79" y2="165"/><line class="e" x1="367.3" y1="101" x2="197.5" y2="165"/><line class="e" x1="367.3" y1="101" x2="312" y2="165"/><line class="e" x1="367.3" y1="101" x2="442" y2="165"/><line class="e" x1="367.3" y1="101" x2="552.5" y2="165"/><line class="e" x1="367.3" y1="101" x2="655.5" y2="165"/><line class="e" x1="1004.3" y1="101" x2="789.5" y2="165"/><line class="e" x1="1004.3" y1="101" x2="954.5" y2="165"/><line class="e" x1="1004.3" y1="101" x2="1092.5" y2="165"/><line class="e" x1="1004.3" y1="101" x2="1219" y2="165"/><line class="e" x1="1370.8" y1="101" x2="1327" y2="165"/><line class="e" x1="1370.8" y1="101" x2="1414.5" y2="165"/><rect class="n" x="788.5" y="22" width="161" height="30" rx="8"/><text class="t" x="869" y="37" dy=".35em" text-anchor="middle">IoT logical design</text><rect class="n" x="290.8" y="86" width="153" height="30" rx="8"/><text class="t" x="367.3" y="101" dy=".35em" text-anchor="middle">Functional blocks</text><rect class="n" x="14" y="150" width="130" height="30" rx="8"/><text class="t" x="79" y="165" dy=".35em" text-anchor="middle">Identification</text><rect class="n" x="160" y="150" width="75" height="30" rx="8"/><text class="t" x="197.5" y="165" dy=".35em" text-anchor="middle">Sensing</text><rect class="n" x="251" y="150" width="122" height="30" rx="8"/><text class="t" x="312" y="165" dy=".35em" text-anchor="middle">Communication</text><rect class="n" x="389" y="150" width="106" height="30" rx="8"/><text class="t" x="442" y="165" dy=".35em" text-anchor="middle">Computation</text><rect class="n" x="511" y="150" width="83" height="30" rx="8"/><text class="t" x="552.5" y="165" dy=".35em" text-anchor="middle">Services</text><rect class="n" x="610" y="150" width="91" height="30" rx="8"/><text class="t" x="655.5" y="165" dy=".35em" text-anchor="middle">Semantics</text><rect class="n" x="916.3" y="86" width="176" height="30" rx="8"/><text class="t" x="1004.3" y="101" dy=".35em" text-anchor="middle">Communication models</text><rect class="n" x="717" y="150" width="145" height="30" rx="8"/><text class="t" x="789.5" y="165" dy=".35em" text-anchor="middle">Request-response</text><rect class="n" x="878" y="150" width="153" height="30" rx="8"/><text class="t" x="954.5" y="165" dy=".35em" text-anchor="middle">Publish-subscribe</text><rect class="n" x="1047" y="150" width="91" height="30" rx="8"/><text class="t" x="1092.5" y="165" dy=".35em" text-anchor="middle">Push-pull</text><rect class="n" x="1154" y="150" width="130" height="30" rx="8"/><text class="t" x="1219" y="165" dy=".35em" text-anchor="middle">Exclusive pair</text><rect class="n" x="1290.3" y="86" width="161" height="30" rx="8"/><text class="t" x="1370.8" y="101" dy=".35em" text-anchor="middle">Communication APIs</text><rect class="n" x="1301" y="150" width="52" height="30" rx="8"/><text class="t" x="1327" y="165" dy=".35em" text-anchor="middle">REST</text><rect class="n" x="1369" y="150" width="91" height="30" rx="8"/><text class="t" x="1414.5" y="165" dy=".35em" text-anchor="middle">WebSocket</text></svg><figcaption style="font-size:.82em;opacity:.72;margin-top:.45rem">Logical design of IoT</figcaption></figure>

Key points.

Identification gives each device a name and address (for example a URI or IPv6 address) so it can be found.
Sensing collects data with sensors, and actuators change the physical state.
Communication links devices, using protocols such as Wi-Fi, Bluetooth and ZigBee.
Computation is the processing unit, such as a microcontroller, that runs the logic and analysis.
Services cover device monitoring, device control, data publishing and device discovery.
Semantics is the ability to extract knowledge and interpret data, using RDF, OWL and similar standards.
Request-response: the client sends a request and the server replies. Publish-subscribe: publishers send data to a broker, which forwards it to subscribed consumers. Push-pull: producers push data to a queue and consumers pull from it. Exclusive pair: a fully duplex, persistent connection between one client and one server.
A REST API uses HTTP methods (GET, POST, PUT, DELETE) on resources and is stateless over request-response. A WebSocket API gives a persistent two-way exclusive-pair connection with low overhead.

Answer frame. Open with the definition of logical design; draw the tree above; then develop the six functional blocks, the four communication models and the two APIs in that order; close with one line that logical design is the abstract view while physical design is the real devices and protocols.

Asked: [7 marks] (May 2023) Discuss about logical design of Internet of Things.

IoT enablers

Definition. Enablers are the technologies that made large-scale IoT practical.

Key points.

Cheap, small and low-power sensors and microcontrollers let anything be connected.
Wireless connectivity (Wi-Fi, Bluetooth, ZigBee, 4G/5G) and IPv6 give every device an address and a link.
Cloud computing supplies storage and processing at scale.
Big-data analytics and machine learning turn the data into insight.

Modern day IoT applications

Definition. IoT applications are real services built on connected devices in daily life and industry.

Key points.

Smart home: lights, locks and thermostats controlled remotely and automatically.
Healthcare: wearables and monitors send patient vitals to doctors.
Agriculture: soil and weather sensors drive irrigation.
Industry and transport: predictive maintenance, fleet tracking and smart cities with traffic and street-light control.

M2M communications

Definition. Machine-to-Machine communication is direct exchange of data between devices, over wired or wireless links, without human involvement.

Key points.

M2M devices usually talk point to point through cellular or proprietary links, not through the open Internet.
A typical M2M system has an M2M device, a communication network and an application server.
Examples are smart meters, ATMs and vending machines reporting to a central system.
M2M is a subset and forerunner of IoT.

IoT vs M2M

Definition. M2M is direct communication between machines over cellular or wired networks; <mark>IoT is a network of things connected to the Internet that share data with cloud applications and people.</mark>

Basis	M2M	IoT
Communication	Point to point between machines	Through the Internet and cloud, using IP protocols
Devices	Same-type devices, often proprietary	Diverse devices from many vendors
Network	Cellular or wired, closed networks	Internet based, open networks
Intelligence	Little; follows fixed rules	High; cloud analytics and decisions
Application	Narrow, one purpose, such as a smart meter	Broad, integrated, such as smart city
Scale	Small, limited nodes	Very large, billions of nodes

Example. M2M: an ATM reporting cash level to the bank server. IoT: a wearable sending health data to a cloud app that alerts the doctor.

Answer frame. Open by defining both terms; draw the table above; give one example each; close with a line that M2M is a closed point-to-point subset while IoT is the open, Internet-wide, data-driven superset.

Asked: [7 marks] (May 2023) Differentiate between M2M and IoT.

IoT vs WoT

Definition. The Web of Things reuses web standards (HTTP, REST, URLs, JSON) to make IoT devices accessible through the application layer.

Key points.

IoT focuses on connecting devices at the network level with many protocols; WoT focuses on the application layer.
WoT treats each device as a web resource with a URL, so a browser can use it.
IoT is the wider concept, and WoT is one way of building on top of it.

IoT reference architecture

Definition. A reference architecture is a common blueprint of layers and functions that IoT systems follow.

Key points.

The device layer holds sensors, actuators and embedded controllers.
The communication layer covers gateways and protocols to the network.
The cloud or service layer handles storage, processing and device management.
The application layer offers user services, with security and management running through all layers.

IoT Network configurations

Definition. A network configuration is the way IoT nodes are connected to each other and to the Internet.

Key points.

Nodes connect over a LAN (short range) that reaches the Internet through a gateway and WAN.
Common topologies are star, mesh and tree.
Star is simple with a central hub, while mesh is self-healing and extends range.

IoT LAN

Definition. An IoT LAN is the local network, in a room, home or factory, that links nearby nodes.

Key points.

It uses short-range links such as Wi-Fi, Ethernet, Bluetooth and ZigBee.
It connects nodes to the gateway.
It offers high speed and low cost but limited coverage.

IoT WAN

Definition. An IoT WAN is the wide-area network that carries data from the gateway over long distances to the cloud.

Key points.

It uses the Internet, cellular (3G/4G/5G), satellite or LPWAN such as LoRa and NB-IoT.
It covers cities or countries at a higher cost than a LAN.
LPWAN gives long range with low power and low data rate.

IoT Node

Definition. An IoT node is a device that has a sensor or actuator, a processor and a communication interface.

Key points.

It senses or controls, processes locally and transmits data.
It is usually battery powered, so it must be low power.
Examples are a temperature sensor board or a smart bulb.

IoT Gateway

Definition. An IoT gateway is a device that connects nodes to the Internet and cloud.

Key points.

It translates between protocols, for example ZigBee or Bluetooth to IP.
It aggregates and filters data before sending it, saving bandwidth.
It provides security, and local processing (edge computing).

IoT Proxy

Definition. An IoT proxy is an intermediary that represents constrained devices to the outside network.

Key points.

It answers requests on behalf of sleeping or low-power nodes, often caching their data.
It translates between web protocols (HTTP) and constrained protocols (CoAP).
It adds access control and shields nodes from direct exposure.

Review of Basic Microcontrollers and interfacing

Definition. A microcontroller is a single chip with a CPU, memory and I/O peripherals that forms the brain of an IoT node.

Key points.

It contains a CPU, RAM, flash (program memory), timers, ADC and GPIO pins on one chip.
Common examples are the 8051, AVR (Arduino) and ARM Cortex-M.
Interfacing connects sensors and actuators through GPIO, ADC (analog input) and serial buses (UART, I2C, SPI).
An ADC converts an analog sensor voltage to a digital number the program can use.

Last-minute revision

IoT: network of sensor-embedded physical objects exchanging data over the Internet.
Logical design = functional blocks + communication models + communication APIs.
Six functional blocks: identification, sensing, communication, computation, services, semantics.
Four communication models: request-response, publish-subscribe, push-pull, exclusive pair.
Two APIs: REST (HTTP, stateless) and WebSocket (persistent, two-way).
M2M is point to point, closed, little intelligence; IoT is Internet based, open, cloud analytics.
WoT reuses web standards at the application layer.
Gateway translates protocols and aggregates data; proxy speaks for constrained nodes.
LAN is short range; WAN is long range (cellular, LPWAN).
Microcontroller = CPU + memory + I/O on one chip; interfaces are GPIO, ADC, UART, I2C, SPI.

Memory hooks

ISCCSS for functional blocks: Identification, Sensing, Communication, Computation, Services, Semantics.
RP-PP-PE for models: Request-response, Publish-subscribe, Push-pull, Exclusive pair.
M2M = machine to machine, closed; IoT = Internet open, brain in the cloud.
Gateway = translator; proxy = stand-in.

Coverage checklist

IoT definition: definition covered.
Characteristics: five characteristics covered.
IoT conceptual and architectural framework: four layers covered.
Components of IoT ecosystems: components covered.
Physical and logical design of IoT: covers the May 2023 logical design question.
IoT enablers: covered.
Modern day IoT applications: covered.
M2M communications: covered.
IoT vs M2M: covers the May 2023 differentiate question.
IoT vs WoT: covered.
IoT reference architecture: covered.
IoT Network configurations: covered.
IoT LAN: covered.
IoT WAN: covered.
IoT Node: covered.
IoT Gateway: covered.
IoT Proxy: covered.
Review of Basic Microcontrollers and interfacing: covered.

Account

Internet of Things (CS-803 (C)) - Unit 1 Short Notes

How unit 1 is examined

IoT definition

Characteristics

IoT conceptual and architectural framework

Components of IoT ecosystems

Physical and logical design of IoT

IoT enablers

Modern day IoT applications

M2M communications

IoT vs M2M

IoT vs WoT

IoT reference architecture

IoT Network configurations

IoT LAN

IoT WAN

IoT Node

IoT Gateway

IoT Proxy

Review of Basic Microcontrollers and interfacing

Last-minute revision

Memory hooks

Coverage checklist