IOT IoT Architecture and Design 1 — Questions and Answers
Question 1: Which IoT architecture layer is responsible for collecting raw data from the physical environment?
- Application layer
- Network layer
- Perception/Sensing layer (Correct answer)
- Processing layer
Correct answer: Perception/Sensing layer
The perception or sensing layer is the bottom layer of IoT architecture, comprising physical sensors and actuators that interact with the environment.
Question 2: In a three-tier IoT architecture, what function does the 'middleware' or 'platform' tier serve?
- Directly reading sensor values
- Data aggregation, storage, processing, and providing APIs to the application tier (Correct answer)
- Rendering the user interface
- Powering IoT field devices
Correct answer: Data aggregation, storage, processing, and providing APIs to the application tier
The middleware tier in IoT architecture aggregates sensor data, provides processing, storage, and exposes APIs that application services consume.
Question 3: What is a 'gateway' in an IoT architecture?
- A type of IoT sensor
- A device that bridges communication between field IoT devices and cloud/backend systems (Correct answer)
- A cloud storage service
- A user interface for IoT dashboards
Correct answer: A device that bridges communication between field IoT devices and cloud/backend systems
An IoT gateway connects field devices using local protocols (Zigbee, Bluetooth) to cloud platforms, handling protocol translation and local processing.
Question 4: What is the key design principle of a 'fog computing' architecture in IoT?
- Moving all computation to centralized cloud data centers
- Distributing computation, storage, and networking services between the cloud and IoT edge devices (Correct answer)
- Using only battery-powered devices
- Eliminating the need for cloud services
Correct answer: Distributing computation, storage, and networking services between the cloud and IoT edge devices
Fog computing extends cloud services closer to IoT devices in a distributed hierarchy, reducing latency and bandwidth by processing data between the edge and cloud.
Question 5: Which design pattern involves IoT devices publishing data to a central message broker that distributes it to interested subscribers?
- Request-Response
- Publish-Subscribe (Pub/Sub) (Correct answer)
- Polling
- Peer-to-Peer
Correct answer: Publish-Subscribe (Pub/Sub)
The Publish-Subscribe pattern decouples IoT data producers from consumers through a broker, allowing many subscribers to receive data from many publishers.
Question 6: What does 'device shadow' (also called device twin) provide in IoT cloud architecture?
- A physical backup device
- A persistent virtual state of an IoT device in the cloud, accessible even when the device is offline (Correct answer)
- A secondary cloud region for redundancy
- An encrypted copy of device firmware
Correct answer: A persistent virtual state of an IoT device in the cloud, accessible even when the device is offline
A device shadow stores the last known state of an IoT device in the cloud, allowing applications to interact with the device representation even when the device is disconnected.
IOT IoT Architecture and Design 1
Which IoT architecture layer is responsible for collecting raw data from the physical environment?