104  IoT Requirements and Characteristics

104.1 Learning Objectives

By the end of this chapter, you will be able to:

  • Explain IoT architecture: Understand the complete data flow through IoT system layers
  • Apply minimum requirements: Identify the three essential components every IoT device must have
  • Evaluate IoT characteristics: Assess IoT systems against eleven ideal characteristics
  • Select appropriate technologies: Choose IoT solutions based on application requirements

IoT Overview Series: - IoT Introduction - Getting started with IoT and the Five Verbs - IoT Perspectives and Definitions - Different stakeholder views on IoT - Device Evolution - Embedded vs Connected vs IoT products - IoT History and Paradigm Shifts - Lessons from technology evolution

Deep Dive Chapters: - Application Domains - Industry-specific IoT applications - IoT Use Cases - Real-world implementation examples

104.2 What is Internet of Things (IoT)

Time: ~10 min | Level: Foundational | ID: P03.C01.U03

TipDefinition

The Internet of Things (IoT) is the concept of connecting everyday physical objects to the internet. These objects can range from household appliances to industrial machinery, enabling them to collect, exchange, and act upon data. IoT bridges the physical and digital worlds, making our environments smarter and more responsive.

Simple Definition: At its core, the Internet of Things refers to the interconnection of physical devices with the internet. This connectivity allows these devices to communicate with each other and with users, often improving functionality and efficiency.

Diverse Interpretations: Various researchers and institutions define IoT in slightly different ways. While these definitions may vary, the central idea remains consistent - IoT is about connectivity and data sharing. Importantly, there is no universally “right” or “wrong” definition.

Comprehensive IoT ecosystem infographic showing four interconnected dimensions: Business (revenue models, licensing, market delivery channels), Market (mobility, institutional, facilities, resources and production sectors), Tech (cloud services, value-added apps, system applications, network services, connectivity and device enablement), and User Experience (context awareness, device types, interface modalities). Central cube represents the integration point where relationships, business, market, and technology converge to create complete IoT solutions.
Figure 104.1: Source: Edinburgh Design Course - Principles and Design of IoT Systems

104.2.1 How IoT Works: The Complete Flow

Beginner-Level View: Four Simple Steps

Flowchart showing four steps of IoT operation

Flowchart diagram
Figure 104.2

Real Example - Smart Thermostat:

  1. Sense: Temperature sensor reads 65F (you set target to 72F)
  2. Connect: Thermostat sends data to cloud via Wi-Fi
  3. Process: Cloud compares 65F vs 72F, decides “too cold”
  4. Act: Cloud sends command to turn on heater + alerts your phone

This cycle repeats continuously, keeping your home comfortable automatically!

104.2.2 Examples of IoT Devices

Collage displaying six everyday objects that can be transformed into IoT devices: an electrical plug, microwave oven, washing machine, coffee maker, commercial truck, and recycling bin with sensors
Figure 104.3: A collection of images showing various everyday objects that can become IoT devices
Infographic showing the redesign process for transforming everyday objects into IoT devices. The diagram illustrates key considerations including adding sensors (temperature, motion, light), connectivity modules (Wi-Fi, Bluetooth, Zigbee), processing capabilities (microcontrollers), power management (battery or mains), and user interfaces (apps, voice control).
Figure 104.4: Framework for redesigning everyday objects into connected IoT products
Layered architecture diagram showing IoT system components from bottom to top: Perception Layer with sensors and RFID tags, Network Layer with Wi-Fi and cellular connectivity, Processing Layer with cloud and edge computing, and Application Layer with smart home, healthcare, and city services
Figure 104.5: Conceptual diagram explaining “What is IoT?”
Device Description
Plug A smart plug that can be controlled remotely to turn devices on and off.
Microwave A connected microwave that can be programmed via a smartphone.
Washing Machine A smart washing machine that monitors energy use and sends notifications when cycles are complete.
Coffee Machine A coffee machine that can be set to brew automatically at specific times.
Truck A connected truck equipped with sensors to track location, fuel efficiency, and maintenance needs.
Recycling Bin Smart bins that monitor waste levels and optimize collection schedules.

IoT has become a foundational technology in various fields, transforming how we live and work by making systems more intelligent and interconnected.

104.2.3 Complete IoT Architecture Layers

Flowchart diagram showing IoT architecture layers

Flowchart diagram
Figure 104.6

Complete IoT Ecosystem - Data Flow:

Layer Components Function Example
Physical Layer Sensors (Temperature, Motion, Pressure, Light), Actuators (Motors, Relays, Valves), Smart Objects (Appliances, Vehicles) Sense environment, act on commands Thermostat sensor reads 65F
Edge Layer Gateways, Edge Computing, Protocol Translation Local processing, filtering Gateway converts Zigbee to Wi-Fi
Connectivity Layer Wi-Fi/Ethernet, Cellular (4G/5G), LPWAN (LoRa, Sigfox), PAN (Bluetooth, Zigbee) Data transmission Wi-Fi sends data to cloud
Cloud Layer Data Storage, Analytics and ML, Business Logic, APIs Intelligence, processing ML learns your schedule
Application Layer Mobile Apps, Web Dashboards, Automation Rules, Alerts and Reports User value delivery App shows energy savings

Data Flow: Physical -> Edge -> Network -> Cloud -> Application Command Flow: Application -> Cloud -> Network -> Edge -> Physical (actuators respond)

Comprehensive IoT connectivity landscape diagram showing the full spectrum of communication technologies organized by network range. PAN includes Bluetooth, UWB, Z-Wave, Zigbee. LAN covers Wi-Fi connectivity. WAN includes cellular technologies from 2G/GSM to LTE Advanced.
Figure 104.7: Source: Edinburgh Design Course (Postscapes) - IoT Connectivity Technologies

104.3 Minimum Requirements of IoT

Time: ~7 min | Level: Foundational | ID: P03.C01.U04

To qualify as part of the Internet of Things (IoT), a physical object must meet three minimum requirements: it should start as an everyday object, be enhanced with computational intelligence, and be equipped with internet communication capability. These components ensure the object can perform smart functions and communicate effectively within an IoT ecosystem.

Everyday Thing: The starting point for any IoT device is a physical object commonly found in daily life, such as furniture, appliances, or vehicles. These objects are made “smart” by adding computational and connectivity features.

Computation: Objects must be enhanced with computational capabilities to process data, execute tasks, and enable intelligent behavior. This often involves embedding microprocessors, sensors, and actuators into the object.

Internet Connectivity: Connectivity is the defining feature of IoT devices. It enables them to communicate with other devices, users, or cloud systems via direct or indirect internet communication channels.

Three-component diagram showing the minimum IoT requirements: a physical thing icon (lightbulb), computation icon (microchip), and internet connectivity icon (cloud with wireless signal), connected with plus symbols to illustrate that all three elements are necessary
Figure 104.8: Diagram illustrating the minimum requirements for an IoT device: everyday thing, computation, and internet connectivity

IoT devices transform the ordinary into extraordinary by leveraging computational intelligence and connectivity, enabling seamless integration into smart environments.

Scenario: Your company is launching a smart lock product with annual revenue projections of $50M. The engineering team proposes a design with a physical deadbolt mechanism, a microcontroller for keypad control and motor operation, and Bluetooth connectivity to communicate with smartphones within 30 feet. Marketing wants to call it an “IoT smart lock” and price it at $299 (premium over $150 traditional locks).

Think about: 1. Does Bluetooth-only connectivity truly enable “control from anywhere” marketing promises? 2. What would competitors with Wi-Fi-enabled locks offer that this version cannot?

Key Insight: Understanding the difference between “connected” and “IoT” is critical for product positioning and customer expectations.

Current Design Status: - Thing: Physical deadbolt mechanism - Computation: Microcontroller for control logic - Internet: Only Bluetooth (local wireless, NOT internet)

Classification: This is a Connected Product, not a full IoT device. Bluetooth provides 10-100 feet range (requires proximity), while Internet enables global access.

Real Example - August Smart Lock Evolution: - Version 1.0: Bluetooth only -> Connected Product (30-foot range, $249) - Version 2.0: Bluetooth + Wi-Fi bridge -> IoT Device (remote access, $279) - Version 3.0: Integrated Wi-Fi -> Full IoT (cloud intelligence, remote unlock, $299)

Business Impact: - Connected: Unlock when standing at door, limited value proposition - IoT: Unlock remotely for delivery ($2B package delivery market), monitor access logs, receive cloud alerts, 3x higher customer lifetime value

Scenario: Your logistics company wants to monitor temperature and humidity in 50 warehouses (200,000+ sq ft each) across the country to protect sensitive pharmaceutical inventory worth $2.5B annually. FDA compliance requires documented temperature control. The IT team presents two competing approaches:

Approach A (Wi-Fi): $50 sensors, $10/month/warehouse, 30-second updates, requires Wi-Fi infrastructure Approach B (LoRaWAN): $80 sensors + $200 gateway, $5/month/warehouse, 10-minute updates, 10-year battery

Think about: 1. What happens when temperature drifts out of range in a 200,000 sq ft warehouse with metal racking blocking signals? 2. Is the $30 sensor price difference more important than 5-year operational costs and reliability?

Key Insight: IoT technology selection depends on application requirements, not “newest” or “fastest” technology.

Critical Requirements Analysis:

Warehouse Environment Challenges: - Large buildings (200,000+ sq ft) - Wi-Fi coverage gaps common - Metal racking - blocks Wi-Fi signals, creates dead zones - Power outlets scarce - sensors need battery-powered - Temperature changes slowly - no need for 30-second updates

5-Year Total Cost of Ownership:

Approach Sensors Installation Monthly Ops 5-Year Total
Wi-Fi $10K $15K (Wi-Fi + power) $500/mo ($30K) $55,000
LoRaWAN $16K $3K (simple placement) $250/mo ($15K) $44,000 (20% savings)

Why 10-Minute Intervals Suffice: - Pharmaceutical storage temperature changes gradually (hours, not seconds) - Refrigeration systems have thermal mass - temperature drifts slowly - 10-minute intervals provide ample warning (regulations require hourly checks) - Real-time creates data overload: 1,051,200 readings/year vs 52,560

LoRaWAN Advantages: - Single gateway covers entire warehouse (vs dense Wi-Fi AP deployment) - 10-year battery eliminates power infrastructure ($15K savings) - Excellent signal penetration through metal racking - Dedicated IoT network isolated from business Wi-Fi

104.4 Characteristics of Ideal IoT Systems

Time: ~8 min | Level: Intermediate | ID: P03.C01.U05

What distinguishes a well-designed IoT system from a mediocre one? Understanding the characteristics of ideal IoT implementations helps engineers, designers, and product managers create systems that deliver real value. These eleven characteristics represent design goals that the best IoT solutions strive to achieve.

104.4.1 The Eleven Characteristics of Ideal IoT

Mind map showing eleven characteristics of ideal IoT systems

Mind map diagram
Figure 104.9

This variant shows the 11 characteristics as a priority matrix - different IoT domains prioritize different characteristics:

Priority matrix showing how different IoT domains prioritize characteristics differently

Flowchart diagram
Figure 104.10: How different IoT domains prioritize the 11 characteristics

Why this variant helps: The original mindmap lists all 11 characteristics as equally important. This variant shows the design reality: different applications prioritize different characteristics. A factory needs millisecond response times (Fast), while a farm sensor can wait hours (Growing is more important). Understanding these trade-offs is essential for IoT product design.

Characteristic Description Real-World Example
Ubiquitous Available everywhere, seamlessly integrated across environments Smart lighting works identically at home, office, and hotel
Smart Makes intelligent decisions based on data and context Thermostat learns your schedule and pre-heats before you arrive
Agile Quickly adapts to changing conditions and requirements Factory sensors detect anomaly and immediately adjust process parameters
On Demand Instantly accessible when needed, responsive to user requests Voice assistant responds within milliseconds to commands
Blend into Background Operates unobtrusively, ambient computing that doesn’t demand attention Environmental sensors work silently without user interaction
Secure Protected against cyber threats, data breaches, and unauthorized access End-to-end encryption, secure boot, and regular security updates
Low Maintenance Self-monitoring, self-healing, minimal human intervention required Devices automatically download updates and report health status
Fast Low latency responses, real-time data processing Industrial control systems respond in less than 10ms to sensor inputs
Upgradable Can evolve through OTA updates without hardware replacement Tesla cars gain new features through software updates
Growing Scales seamlessly from prototype to millions of devices Platform handles 10 devices in pilot and 10 million in production
Adaptable Flexible to new use cases, protocols, and integrations Smart home hub supports new device types as they emerge

Trade-off Reality: No single IoT system perfectly achieves all eleven characteristics. Designers must prioritize based on use case:

Use Case Priority Characteristics Acceptable Trade-offs
Medical Wearable Secure, Fast, Low Maintenance May sacrifice Ubiquitous (works only in certain regions)
Smart Agriculture Low Maintenance, Growing, Adaptable May sacrifice Fast (hourly updates sufficient)
Industrial Control Fast, Secure, Agile May sacrifice Blend into Background (operators need visibility)
Consumer Smart Home On Demand, Upgradable, Blend into Background May sacrifice Growing (fixed home size)

Design Principle: Identify your 3-4 must-have characteristics and ensure they’re exceptional, rather than achieving mediocrity across all eleven.

Scenario: You’re evaluating two smart thermostat products for a commercial building deployment (500 units across 50 floors):

Product A: Fast response (2-second latency), excellent mobile app, requires manual firmware updates via USB, single-building deployment limit, proprietary protocol.

Product B: Slower response (8-second latency), basic web interface, automatic OTA updates, unlimited scalability, supports multiple protocols (Wi-Fi, Zigbee, BACnet).

Question: Which product better meets ideal IoT characteristics for this commercial deployment?

Answer: Product B wins because: - Growing: Unlimited scalability handles future expansion (Product A’s single-building limit is disqualifying) - Low Maintenance: OTA updates across 500 devices vs. USB updates (500 x manual visits = untenable) - Upgradable: Automatic firmware ensures security patches reach all devices - Adaptable: Multi-protocol support integrates with existing BACnet building management systems

Speed Trade-off is Acceptable: HVAC systems have thermal mass - 8-second response is adequate for temperature control (rooms don’t heat/cool in seconds). 2-second advantage provides no practical benefit.

Product A’s mobile app is irrelevant for commercial building operators who use centralized building management dashboards, not individual phone apps.

This illustrates why prioritizing the right characteristics for your use case matters more than raw feature comparison.

104.5 Summary

In this chapter, you learned:

  • IoT works in four steps: Sense -> Connect -> Process -> Act, repeating continuously
  • Three minimum requirements define IoT: Thing + Computation + Internet connectivity
  • Eleven characteristics distinguish ideal IoT systems: Ubiquitous, Smart, Agile, On Demand, Blend into Background, Secure, Low Maintenance, Fast, Upgradable, Growing, Adaptable
  • Trade-offs are necessary: Different applications prioritize different characteristics
  • Technology selection should be driven by requirements, not by “newest” or “fastest”

104.6 What’s Next?

Continue to IoT Perspectives and Definitions to understand how different stakeholders view IoT and explore formal definitions from academia and industry.