VEL TECH MULTI TECH Dr. RANGARAJAN Dr.

SAKUNTHALA ENGINEERING
COLLEGE
(An Autonomous Institution)
Degree/Branch: B.E./CSE Year / Sem: III/V
191CSV65 - INTERNET OF THINGS – All 5 Units QB

UNIT – 1 / Introduction to IoT

PART A (Objective Type - 1 Mark)

Internet of Things - Physical Design- Logical Design- IoT Enabling Technologies - IoT
Levels & Deployment Templates - Domain Specific IoTs - IoT and M2M - IoT System
Management with NETCONF- YANG- IoT Platforms Design Methodology.

1 Out of this, which of the following deals with IoT? CO1.1 CL 1

a) Connecting Things b) Connection of Things
c) Connection of computers d) Connecting computers
2 Which of the following is not an IoT platform? CO1.1 CL 1
a) Amazon Web Services b) Microsoft Azure
c) Salesforce d) Flipkart
3 In what way, IoT devices can exchange data? CO1.1 CL 1
a) Directly b) Indirectly c) Both a & b d) None of a & b
4 How many open interfaces are there to connect with Service Capability layers? CO1.1 CL 1
a) One b) Two c) Three d) NIL
5 The "Things" in IoT refers to physical objects that have ________ identifiers and can CO1.2 CL 1
sense and communicate with their external environment
a) Double b) Triple c) Unique d) No
6 An equation of internet of things......... CO1.2 CL 1
a) physical object + controller sensor and actuator + internet
b) controller sensor and actuator + internet
c) physical object + internet
 d) physical object + controller + internet
7 Out of the following, which is used in HTTP protocol? CO1.2 CL 1
a) Application Layer b) Link Layer
b) Network layer d) Transport Layer
8 Which of the following is not an element of IoT? CO1.3 CL 1
a) People b) Process c) Security d) Things
9 Which of the following is NOT a Communication protocol? CO1.3 CL 1
a) ZigBee b) Bluetooth c) ModBus d) IEEE 801.15.6
10 Which of the following is not a fundamental component of an IoT system? CO1.3 CL 1
a) Sensors b) Connectivity and data processing
c) User interface d) Transformer
11 In IoT environment, the data processing happens at___. CO1.3 CL 1
a) cloud b) locally c) both a & b d) None of a& b
12 IPv6 is implemented in _______________ layer CO1.3 CL 1
a) devices b) services c) application d) network
13 Which protocol is the backbone of IoT systems and enables network connectivity and CO1.4 CL 1
linking to applications?
a) Network b) Communication c) Application d) Cloud
14 Out of the following, mention the use of WSN to monitor the health of buildings and CO1.4 CL 1
bridges
a) Surveillance system b) Structural health monitoring system
c)Soil moisture monitoring system d)Weather monitoring system
15 A level-6 IoT system has _______________. CO1.5 CL 1
a) multiple independent end nodes b) multiple end nodes and one coordinator node
c) multiple nodes only d) All the three
16 A level-4 IoT system has______. CO1.5 CL 1
a) Single node b) two nodes c) multiple nodes d) None of a, b & c
17 The data in IoT is collected in the cloud which can be ________. CO1.6 CL 1
 a) Public b) private c) hybrid cloud d) all the three
18 One of the following is not a cloud service provider. Identify it. CO1.6 CL 1
a) Google Compute Engine b) Red Hat Linux
c) Amazon Web Services d) Microsoft Azure
19 The main function of M2M Service Bootstrap Function is to facilitate the CO1.7 CL 1
bootstrapping___.
a) Security credentials b) routing credentials c) network credentials d) data credentials
20 M2M Authentication Server uses ______ for authorization of communication. CO1.7 CL 1
a) Biometric b) Iris detection c) Face recognition d) Digital certificate
21 In M2M, the _____________ can use either wired or wireless networks (IP based). CO1.7 CL 1
a) Communication Network b) M2M Area Network
c) Local Network d) all the above
22 The communication network in M2M can be used ___________ CO1.7 CL 1
a) Wireless medium b) Wired medium
c) Both d) None
23 NETCONF is an __________ network management protocol CO1.8 CL 1
a) IEEE b) ETSI c)IETF d) None
24 How much number of components requires to managing the IoT using NETCONF- CO1.8 CL 1
YANG?
a) 7 b) 8 c) 9 d) 6
25 Which of the following language, YANG is said to be? CO1.8 CL 1
a) tree-structured b) object-oriented c) multinational d) European
 PART- B

4 Marks

1 Consider the following scenario. “a relay switch connected to an IoT device can turn an
appliance on/off based on the commands sent to the IoT devices over the internet”. Utilize
the IoT devices which are involved in relay switch with diagrammatic representation.
CO1.1 CL3.

Answer:
Diagrammatic representation of IoT devices which are involved in this real time scenario

2 “For identification, sensing, actuation, communication and management in an IoT , a

number of functional blocks are described”, show the necessary functional blocks inferred
in an IoT system. CO1.2 CL2.

Answer:

Necessary functional blocks in an IoT system

3 In which communication model, the following concept applies: “When the server receives a
request, it decides how to respond, fetches the data, retrieves resource representations,
prepares the response and then send sends the response to the client” –justify with a neat
diagrammatic representation. CO1.3 CL3.

Answer:

Request-Response is a communication model in which the client sends request to the server and
the server responds to the request.

Request-Response Communication model

4 Make use of IoT enabling technology, explain the concept of “provisioning of computing,
networking, storage resources on demand and providing these resources as metered services
to the users, in a PAY AS YOU GO model” CO1.4 CL3

Answer:

Cloud computing allows for the provisioning of computing, networking, and storage
resources on demand. This means that users can quickly and easily access and utilize these
resources whenever they need them, without the need for upfront investment in infrastructure.
In the context of IoT, cloud computing plays a crucial role in supporting the scalability and
flexibility required by IoT applications. Following the concept of provisioning and metered
services in a PAY AS YOU GO model works:

i)Provisioning Resources: Cloud service providers – e.g., Amazon Web Services (AWS)
 ii)Metered Services: Cloud providers typically offer a PAY AS YOU GO model, where users pay
only for the resources they consume. These resources are metered, meaning users are charged
based on the actual usage and duration of resource utilization.

iii)Scalability and Flexibility: Users can easily scale up or down their resource allocations based
on changing demands. For example, during peak periods of data influx, additional computing
resources can be provisioned to handle the increased load, and then scaled down when the load
reduces.

Overall, the concept of provisioning resources on demand and providing them as metered
services in a PAY AS YOU GO model is a key aspect of cloud computing, enabling the scalability,
flexibility, and cost efficiency required by IoT deployments.

5 Outline with an example in which IoT system level has a single node/device that performs
sensing, stores data, performs analysis and host the application. CO1.5 CL2

Answer:

A level 1 IoT system has a single node that performs sensing, stores data etc.,
6 You are assigned with the construction of a multiple node IoT application where-in one of
the nodes act as a coordinator. Explain it with neat diagram CO1.5 CL2

Answer:

- A level-5 IoT system has multiple nodes and one coordinator node.
- The end node performs sensing and actuation.

- Coordinator node collects data from the end nodes and sends to the cloud.

7 Examine the types of data generated by a forest fire detection system. Describe any one of
the alternative approach for storing the data. CO1.6 CL4

Answer:

A forest fire detection system generates various types of data to monitor and assess the
potential occurrence and spread of wildfires. The data collected typically falls into the following
categories:
  Environmental Data
 Spatial Data
 Sensor Data
 Communication Data

Environmental Data:

This includes information about weather conditions and atmospheric variables such as
temperature, humidity, wind speed, wind direction, precipitation, and air pressure. These factors
are crucial in assessing fire risk and predicting fire behaviour.

Sensor Data:

The system may have various sensors scattered throughout the forest, including infrared cameras,
smoke detectors, and heat sensors, which can provide real-time information about potential fire
occurrences and early signs of fire ignition.

Alternative approach for storing the data:

Cloud Storage: Data can be stored in cloud-based storage systems like Amazon S3, Google Cloud
Storage, or Azure Blob Storage. These platforms offer scalable and cost-effective solutions for
managing large volumes of data.

8 With a neat diagram show the end-to-end architectures for M2M systems comprising of
M2M area networks, communication network and application domain. CO1.7 CL3

Answer:

Machine-to-Machine (M2M) refers to networking of machines (or devices) for the purpose of
remote monitoring and control and data exchange.
9 Show the diagrammatic representation of communication in IoT is ip-based whereas M2M
uses non-ip based networks. CO1.7 CL2

Answer:

10 In order to have a good IoT network management system, Infer the network operator
requirements based on your understanding? CO1.8 CL2

Answer:

The following are the points which provide the overview of the network operator requirements

 Ease of use
 Distinction between configuration and state data
 Fetch configuration and state data separately
 Configuration of the network as a whole
 Configuration transactions across devices
 Configuration deltas
 Dump and restore configurations
 Configuration validation
 Configuration database schemas
 Comparison configurations
 Role-based access control lists
 Multiple configuration sets
 Support for both data-oriented and task-oriented access control
11 “Managing multiple devices within a single system requires advanced management
capabilities”-justify the statement by illustrating the diagram. CO1.8 CL3

Answer

Using IoT device management with NETCONF-YANG, one can manage multiple devices with a
single system

12 In IoT design methodology, the system purpose, behaviour and requirements are captured.
Apply these requirements in smart home automation system and explain it. CO1.9 CL3

Answer:

Apply the IoT design methodology of a smart home automation system, the purpose and
requirements for the system may be described as follows:

 Purpose: A home automation system that allows controlling of the lights in a home
remotely using a web application.
  Behaviour: The home automation system should have auto and manual modes.
-Auto mode: the system measures the light level in the room and switches on the
light when it gets dark. -
Manual mode: the system provides the option of manually and remotely switching on/off
the light.
 System Management Requirement: the system provide remote monitoring and control
functions.
 Data Analysis Requirement: the system should perform local analysis of the data.
 Application Deployment Requirement: the application should be deployed locally on the
device, but should be accessible remotely.
 Security Requirement: the system should have basic user authentication capability

PART - C
12 Marks
1 “IoT devices can exchange data with other connected devices and applications based on
temporal and space constraints”-Apply the IoT protocols which are involved in transferring
the data with respect to various layers. CO1.2 CL3
Answer:
IoT Protocols diagram -4 marks
 Each layer carries 2 marks:
Various layers: -
Application layer –
Transport layer
Network layer
Link layer
2 Determine the various communication models that can be used for weather monitoring
system. Which is a more appropriate model for this system? CO1.3 CL4
Answer:
Various communication model with definition of IoT level 1 - 6. – 3 marks
Diagram – 5 marks

Level -6 is most appropriate model for weather monitoring system with explanation – 3 marks
3 Summarize an overview of some of the enabling technologies which play a key role in IoT.
With necessary examples- explain it. CO1.4 K2
Answer:
IOT ENABLING TECHNOLOGIES
IoT is enabled by several Technologies: -

 Wireless Sensor Networks (2 marks)

 Cloud Computing (3 marks)
 Big Data Analytics (3 marks)
 Communication Protocols (2 marks)
 Embedded Systems (2 marks)

4 Compare IoT levels 4,5 and 6 systems in terms of Database management, complexity level,
involvement of nodes in the system CO1.5 CL4
Answer:
Various communication model from level 4 to level 6. Each level carries 4 marks
5 While designing a domain specific IoT, each domain has a wide variety of IoT applications.
Out of these applications, explain “home automation system” with an examples CO1.6 CL4
Answer:

Home automation system:

Examples:
Smart lighting
Smart appliances
Intrusion detection
Smoke /gas detector.
Each example carries 3 mark

6 Both IoT and M2M involve networking of machines, explain the differences which are in
following technologies i) communication protocols ii) Machines in M2M vs Things in IoT iii)
Hardware vs Software Emphasis CO1.7 K4
Answer:
i) communication protocols – 4 marks

ii) Machines in M2M vs Things in IoT - 4 marks

iii)Hardware vs Software Emphasis -4 marks
7 From your understanding, analyze the roles of the various components which are involved
in generic approach of IoT device management with NETCONF-YANG. CO1.8 CL4

Answer:

Diagram – 5 marks
explanation – 7 marks
8 Develop an IOT design for home automation system and justify how Privacy and Security is
provided in your prototype CO1.9 CL3
Answer:
Diagram – 6 marks
explanation – 6 marks
 UNIT-2 / IoT Architectures
PART A (Objective Type - 1 Mark)

IoT Architectures: oneM2M, IoT World Forum (IoTWF) and Alternative IoT models,
Simplified IoT Architecture and Core IoT Functional Stack, Fog, Edge and Cloud in IoT,
Functional blocks of an IoT ecosystem, Sensors, Actuators, Smart Objects and Connecting
Smart Objects.

1 IoT devices are naturally vulnerable to ________ threats. CO2.1 CL1

a) Sensors b) Heterogeneity c) Security d) Connectivity

2 How many types of nodes are there in M2M? CO2.1 CL1

a) One type b) Two type c) Three types d)Four types
3 How many domain of the oneM2M architecture divides IoT functions? CO2.1 CL1
a) One b) Two c) Three d) Four
4 _____________ brings connectivity to IoT networks. CO2.2 CL1
a) HTTP b) HTML c) IP, TCP, and UDP d) None
5 What is the functionality of IoT gateways? CO2.2 CL1
a) Addressing b) Switching c) Routing d) None
6 IoT gateway must provide __________ CO2.2 CL1
a) Protocol abstraction b) Data storage
c) Security with hardware d) Simple and fast installation

7 Which of the following is not a fundamental component of an IoT system? CO2.3 CL1
a) Sensors b) Connectivity and data processing c) User interface d) Transformer

8 Which of the following is false about the IoT components? CO2.3 CL1
a) A light sensor (photo-resistor) is an analog sensor
b) A microphone is a digital sensor
c) A push button is a digital sensor d) A keyboard is a digital sensor
9 Which service permits the changes to the IoT services? CO2.3 CL1
a) Update b) Registered service status c) Enable from suspension d) Enable

10 IOT and cloud computing has ______ relationship. CO2.3 CL1

a) Physically b) Graphically c) Coding d) Complementary
11 Simplified IoT architecture consists of: CO2.3 CL1
a) Core IoT functional stack Offset
b) IoT Data management & compute stack
c) Only a
d) Both a & b
12 ________ helps in collaborate in IOT development. CO2.4 CL1
a) Physical computing b) Cloud computing
c) Mechanism d) Chemical computing
13 Edge computing is often referred to as the “Fog” layer and is discussed in the section CO2.4 CL1

________
a) Fog Computing b)Fog c) computing d) none
14 ____________ Computing is the extension of cloud computing. CO2.5 CL1
a) Mobile cloud computing b) Mist computing
c) Fog computing d) Cloud computing
15 Which of the following computing emphasizes proximity to end user? CO2.5 CL1
a) Mist computing b) Cloud computing c) Edge computing d) Fog computing
16 ______practice of using a network of remote servers hosted on the Internet of store. CO2.5 CL1
a) Mist computing b) Fog computing c) Cloud computing d) Mobile cloud computing
17 In an application the smartness includes sensor objects in the following layer. CO2.6 CL1
a) Physical layer b) Network layer c) Application layer d) Data Link
Layer

18 A _______ tends to convert physical attribute to an electrical signal. CO2.7 CL1

a) actuator b) compiler c) sensor d) motors
19 Which of the following is not a sensor in IoT? CO2.7 CL1
a) BMP280 b) DHT11 c) Photo-resistor d) LED

20 Which of the following is used to capture data from the physical world in IoT devices? CO2.7 CL1
a) Sensors b) Actuators c) Microprocessors d) Microcontrollers
21 Potentiometer is which of the following types of sensor? CO2.7 CL1
a) Speed sensor b) Light sensor c) Position sensor d) Force sensor
22 Out of the following, which sensor measures the moisture content of an environment? CO2.7 CL1
a) Soil sensor b) Temperature sensor c) Humidity sensor d) All
23 Electric motor protection has which sensor? CO2.7 CL1
a) Pressure b) Touch c) Temperature d) Humidity
24 Which devices include the necessary conversion of analog electrical signals into digital CO2.8 CL1
signals?
a) Actuator b) Sensor c) Tags d)None

25 ____________examines the importance of signal propagation and distance CO2.9 CL1

a) Range b) latency c) Bands d) actuators
 PART- B

4 Marks

1 Take a closer look at some of the differences between IT and IoT networks, explain the points
with a focus on the IoT requirements that are driving new network architectures, and consider
what adjustments are needed. CO2.1 CL2 [pgno: 29]

Answer:
2 While the oneM2M architecture may seem simple and somewhat generic at first glance, it is
very rich and promotes interoperability and supports a wide range of IoT technologies. Examine
each of the domains in turn with neat presentation. CO2.1 CL4[pgno: 34]

Answer:

3 One of the basic principles of the IoTWF reference model is that information processing is
initiated as early and as close to the edge of the network as possible. Highlights the functions
handled by Layer 3 of the model. CO2.2 CL3[pgno: 37]

Answer:
4 Outline the core IoT functional stack that can be expanded into sub layers containing greater
detail and specific network functions. CO2.4 CL2 [pgno: 42]

Answer:

5 From an architectural standpoint, classify the variety of smart object types, shapes, and needs
drive the variety of IoT protocols and architectures? CO2.4 K2 [pgno: 44]

Answer:
6 “Just as clouds exist in the sky, fog rests near the ground”- justify the sentence with the defining
characteristics of fog computing. CO2.5 CL3 [pgno: 67]
 Answer:

7 “If cloud exist in the sky, and fog sits near the ground, then mist is what actually sits on the
ground”-Justify the sentence with an example of smart meters. CO2.3 [pgno: 68]

Answer:
8 With a neat diagram, illustrates the hierarchical nature of edge, fog, and cloud computing across
an IoT system.CO2.2 K4 [pgno: 69]

Answer:

9 Categorize the most useful classification scheme for the pragmatic application of sensors in an
IoT network with necessary examples. CO2.7 K4 [pgno: 77]

Answer:
 Show the diagrammatic representations of smart phone with various sensors involved and
explain any four with their description. CO2.7 CL2 [pgno: 80]
10
Answer:

11 “Categorizing actuators is quite complex, so this is by no means an exhaustive list of

classification scheme”. Tabulate the most commonly used classification is based on energy type.
CO2.8 K4 [pgno: 82]

Answer:
 Outline an example of data aggregation function in a WSN where temperature readings from a
logical grouping of temperature sensors are aggregated as an average temperature
12
reading.CO2.9 CL2 [pgno: 90]

Answer:

The above diagram shows an example of such a data aggregation function in a WSN where
temperature reaings from a logical grouping of temperature sensors are aggregated as in average
temperature reading
 PART - C
12 Marks
1 Consider the following scenario,” you might want to automate your HVAC system by connecting
it with wireless temperature sensors spread throughout your office. You decide to deploy sensors
that use LoRaWAN technology. The problem is that LoRaWAN network and the BACnet system
of your HVAC and BMS run on are completely different systems and have no natural connection
point”. With a neat representation, explain in which situation, one M2M common services
architecture comes in. CO2.1 CL3 [pgno: 33]
Answer:
Explanation – 6 marks
Diagram – 6 marks

2 In 2014 the IoTWF architectural committee published a seven-layer IoT architectural reference
model. Each of the seven layers is broken into specific functions and security encompasses the
entire model. Make use of this reference model, show the standardized architecture published by
the IoTWF. CO2.2 CL3 [pgno: 35]
Answer:
Explanation- 5 marks
Diagram- 7 marks
3 “Rather, the intention is to simplify the IoT architecture into its most basic building blocks and
then to use it as a foundation to understand key design and deployment principles that are applied
to industry- specific use cases.”- Illustrate the simplified IoT model presented with the functional
blocks. CO2.3 CL2 [pgno: 41]
Answer:
Explanation- 7 marks
Diagram- 5 marks
4 “In most cases, the “thing” interacts with an external system to report information that the smart
object collects, to exchange with other objects, or to interact with a management platform.” From
an architectural standpoint, explain the components that have to work together for an IoT
network to be operational. CO2.4 CL4 [pgno: 43]
Answer:
Explain – Core IoT functional stack – 6 marks
Diagram – 6 marks

5 Outline the IoT data management and compute stack for “Analysing IoT data close to where it is
collected minimizes latency, offloads gigabytes of network traffic from the core network, and
keeps sensitive data inside the local network. CO2.4 CL2 [pgno: 65]
Answer:
Explain – IoT Data Management and Compute Stack – 6 marks
Diagram – 6 marks
6 “For the creation of a smart city- a broad network of connected, interdependent devices and
technologies are applied”. Make use of this example and show the simplified view of basic building
block of an IoT ecosystem. CO2.6 CL2

Answer:

Explanation- 8 marks
Diagram – 4 marks

7 Develop the use case to highlight the power of sensors and IoT is in the area of precision
agriculture (smart farming), which uses a variety of technical advances to improve the efficiency,
sustainability and profitability of traditional farming practices. CO2.7 CL3 [pgno: 79]
Answer:
Explanation:
 Sensors involved in smart farming – 8 marks

Technical advances – 4 marks

8 Actuators are natural complements to sensors. Demonstrates the symmetry and complementary nature
of these two types of device and explain with necessary examples. CO2.8 K2 [pgno: 81]
Answer:
Explanation- 7 marks
Example – 5 marks
 UNIT-3 / IoT Protocols
PART A (Objective Type - 1 Mark)

IoT Access Technologies: Physical and MAC layers, topology and Security of IEEE
802.15.4, 802.15.4g, 802.15.4e, 1901.2a, 802.11ah and LoRaWAN, Network Layer: IP
versions, Constrained Nodes and Constrained Networks, Optimizing IP for IoT: From
6LoWPAN to 6Lo, Routing over Low Power and Lossy Networks.

1 How many Levels in the IoT architecture? CO3.1 CL1

a) Four Levels b) Five Levels c) Six Levels d) Seven Levels
2 Network topology with a central hub or switch is ______ CO3.1 CL1
a) Mesh b) Token ring c) Star d) Token bus
3 Which technique allows transceiving of IPv6 packets over IEEE 802.15.4 in 6LoWPAN? CO3.2 CL1
a) Header compression b) Address Translation c) Both a & b d) None
4 Which of the following modulation scheme used in IEEE 802.15.4? CO3.2 CL1
a) GMSK b) OQPSK c) QPSK d) PSK
5 IEEE 802.15.4 Physical Layer focuses on ______ CO3.2 CL1
(a) Transmission possibility (b) MAC reliability and unbounded latency

(c) Communication Models (d) data frames

6 The payload size of the IEEE 802.15.4 is _____ CO3.2 CL1

a) 0-127Bytes b) 0-2047 Bytes c) 0-1000 Bytes d) 0-1800 Bytes
7 The physical layer transmission option(s) in IEEE 802.15.4 is ____ . CO3.2 CL1
a) 2.4 GHz, 16 channels, data rate of 250 kbps
b) 915 MHz, 10 channels, data rate of 40 kbps
c) 868 MHz, 1 channel, data rate of 20 kbps
d) All the above
8 In IEEE 802.15.4 MAC layer, the purpose of the Beacon frame is _____. CO3.2 CL1
 a) Network Identification b) Security c) Network Integration d) none of the
above
9 In IEEE 802.15.4 MAC, to improve the security, the following security algorithm is used CO3.2 CL1
______.
(a) RSA Algorithm (b) AES Algorithm (c) DES Algorithm (d) None
10 Which is not the function of ZigBee used with IEEE 802.15.4 standard ? CO3.2 CL1
a) Network routing b) Address translation
c) Channel acquisition d) Packet segmentation
11 Following layer of ZigBee is shared FOR alliance with IEEE 802.15.4 . CO3.2 CL1
a) Network layer b) Data link layer c) Application layer d) Mac layer
12 The error protection was improved in IEEE 802.15.4g by evolving the CRC of___bits. CO3.2 CL1
(a) 8 to 12 (b) 12 to 16 (c) 16 to 32 (d) 8 to 32
13 In IEEE 1901.2a, Data rates can scale up to ______ kbps. CO3.3 CL1
(a) 25Kbps (b) 50 Kbps (c) 250 Kbps (d) 500 Kbps
14 LoRaWAN topology is described as a __________ topology. CO3.5 CL1
(a) “STAR” (b) “MESH” (c) “PEER to PEER” (d) “star of stars”
15 In LoRaWAN Security arrangements, NwkSKey ensures ______ CO3.5 CL1
(a) Data frame (b) Data integrity (c) Digital data (d) IPv6
16 The maximum transmission unit (MTU) for an IPv6 network must be _____bytes. CO3.6 CL1
(a) 1280 (b) 10218 (c) less than 1280 (d) less than 128
17 Which of the following is a major concern in IPV4 addressing? CO3.6 CL1
a) Reliable data transmission b) Only Addressing
c) Multicast Addressing d) All of these
18 In Constrained Nodes, communications are enabled only when needed to send data. This CO3.7 CL1
is referred as _____________ Mode.
(a) Sleeping (b) Low Power (c) Dead (d) None of the above
19 In Constrained Networks, the Packet Delivery Rate (PDR) oscillates between _____ CO3.7 CL1
percentages.
(a) 10 to 15 (b) 20 to 25 (c) high to Very high (d) low and high
20 Which layer is the communication layer that connects the IoT devices with WAN? CO3.7 CL1
 a) Internet layer b) Application layer c) Network layer d) Sensor layer
21 Which of the following is not a type of header in 6LoWPAN? CO3.8 CL1
a) Header Compression b) Mesh Addressing
c) Fragmentation d) Flow label
22 6LoWPAN Adaption layer contains____. CO3.8 CL1
a) Header compression b) Fragmentation c) Layer 2 forwarding d) All of these
23 The main focus of 6Lo working group is on _____. CO3.8 CL1
(a) IPv4 Connectivity (b) IPv6 Connectivity
(c) Communication ability (d) Security
24 Which of these is a routing protocol for low power lossy networks over IPv6? CO3.9 CL1
a) RPL b) OSPF c) RIP d) All
25 What is the standard form of LLN? CO3.9 CL1
a) Low Lossy Network b) Low power Lossy Network c) Low Level Network d) None
 PART- B

4 Marks

1 “The IEEE 802.15.4 PHY and MAC layers are the foundations for several networking
protocol stacks”. Show some of the most well-known protocol stacks based on 802.15.4.
CO3.2 CL2 [pgno: 109]

Answer:
2 Apply ZigBee IP Protocol stack for the following examples,” Smart metering and residential
energy management systems”. CO3.2 CL3 [pgno: 111]

Answer:

3 Make use of four types of MAC frames specified in 802.15.4. Show the diagrammatic
representation of IEEE 802.15.4 MAC format. CO3.2 CL3 [pgno: 112]

Answer:
4 “The IEEE 802.15.4g – 2012 PHY is similar to the IEEE 802.15.4 PHY”-With a neat diagram
of IEEE 802.15.4g/e MAC Frame Format, explain the similarities and differences between
them. CO3.2 CL4 [ pgno: 122]

Answer:

5 “The feature list of 802.11ah MAC layer is focused on power consumption and mechanisms
to allow low-power Wi-Fi stations to wake up less often and operate more efficiently”. Infer
some enhancements and features specified by IEEE 802.11ah for the MAC layer. CO3.3 CL2
pgno: 131
 Answer:

6 “One of the key components brought from 802.15.4e to 190 1.2a is information elements”.
With IE support, show the figure that provides an overview of the general MAC frame
format for 190 1.2. CO3.4 CL3 pgno: 126

Answer:
7 Demonstrate how the LoRaWAN data rates can vary depending on the associated spreading
factor for the two main frequency bands, 863-870 MHz AND 902-928 MHz. CO3.5 CL2
pgno: 136

Answer:
8 Categorize the classification of constrained nodes that helps when evaluating the IP adoption
versus adaptation model. CO3.7 CL4 pgno: 155

Answer:

9 “IPV6- only adaptation layers for some physical and data layers for recently standardized
IoT protocols support only IPV6”- Justify the statement by outlining the optimizing IP for
IoT using an adaptation layer. CO3.8 CL2 pgno: 159

Answer:
10 With a neat diagram shows an example of an IoT protocol stack using the 6LoWPAN
adaptation layer beside the well-known IP protocol stack for reference. . CO3.8 CL3

pgno: 160

Answer:

11 Outline the following concept in a diagrammatic manner, “DAO and DIO messages move
both up and down the DODAG, depending on the exact message type”. CO3.9 CL3

pgno: 170

Answer:
12 “RPL defines a large and flexible set of new metrics and constraints for routing in RFC
6551”. Show some of the RPL routing metrics and constraints developed for supporting
powered and battery-powered nodes. CO3.9 CL2 pgno: 171

Answer:
 PART - C
12 Marks
1 “IEEE 802.15.4 standard – supports an extensive number of PHY options that range from
2.4GHZ to sub-GHz frequencies in ISM bands –manages access to the PHY channel by defining
how devices in the same area will share the frequencies allocated”. Identify the layers and
explain it with a neat presentation. CO3.2 CL4 pgno: 113
Answer:
Explanation:
Physical Layer with description- 5 marks
Additional PHY communication option-3 marks
Diagram- 4 marks

2 “IEEE 802.15.4g focuses mainly on improvements to the PHY layer, while IEEE 802.15.4e
targets the MAC layer”- Justify this statement with a neat diagrammatic representation along
the security in both standards. CO3.2 CL3 pgno: 123
Answer:
Explanation – 6 marks
Diagram – 6 marks
3 IEEE 190 1.2a is an open PHY and MAC standard approach to enable the use of Narrowband
Power Line Communication. Examine the set of use cases for this standard depends on the
physical power lines that interconnect the devices. CO3.4 CL4 pgno: 126
Answer:
Explanation of:
PHY – 3 marks
MAC – 3 marks
Diagrams- 6 marks

4 LoRaWAN topology is described as a “star of stars” topology. Illustrate the infrastructure

consists of endpoints exchanging packets through gateways acting as bridges, with a central
LoRaWAN network server. CO3.5 CL2 pgno: 138
Answer:
Explanation – 6 marks
Diagram – 5 marks
5 “From a security perspective, LoRaWAN offers AES authentication and encryption at two
separate layers” – justify the statement by outlining the security in a LoRaWAN deployment
which applies to different components of the architecture. CO3.5 CL3 pgno: 140
Answer:
Explanation – 6 marks
Diagram – 6 marks
6 “While the Internet Protocol is key for a successful IoT, constrained nodes and constrained
networks mandate optimization at various layers on protocols of the IP architectures”- explain
the TCP/IP layers where optimization is applied and show how the comparison of an IoT
protocol stack utilizing 6LoWPAN and an IP protocolstack.CO3.7 K4 pgno: 159
Answer:
Optimization:
Diagram – 4 marks
Explanation – 3 marks
Comparison diagram – 5 marks

7 The 6LoWPAN working group published several RFCs, but RFC 4994 is foundational because
it defines frame headers for the capabilities of header compression, fragmentation and Mesh
addressing. Outline the necessary diagrams involved in 6LoWPAN header stacks.CO3.8 CL3
pgno: 161
Answer:
Diagrams:
Header stacks – 3 marks
Header compression – 3 marks
Fragmentation- 3 marks
Mesh addressing – 3
8 Analyze the working of Routing over Low-Power and Lossy Networks to evaluate all Layer 3 IP
routing protocols and determine the needs and requirements for developing a routing solution
for IP smart objects. CO3.9 CL4 pgno: 167
Answer:
Explanation – 6 marks
Diagrams- 6 marks
 UNIT-4 / Design and Development
PART A (Objective Type - 1 Mark)

Design Methodology, Embedded computing logic, Microcontroller, System on Chips, IoT

system building blocks, Arduino, Board details, IDE programming, Raspberry Pi,
Interfaces and Raspberry Pi with Python Programming .

1 An Embedded system consists of ____. CO4.1 CL1

a) Low cost computer b) Sensor c) actuator d) all the above
2 One of the following is not a µController. Identify it. CO4.2 CL1
a) Motorola 68HC11 b) PIC 16F84 c) Atmel 8051 d) Intel 8085
3 The most important difference between µControllers and µprocessor is: CO4.3 CL1

a) internal read and writable memory b) Processor

c) Power supply d) None

4 A ________ combined a required electronic circuit of various computer components CO4.4 CL1
onto

a single integrated chip.

a) source on chip b) system on change c) system on chip d) source on change

5 System on Chip provides value by________ functionality CO4.4 CL1

a) minimizing b) maximizing c) normal d) none

6 Identify SoC from the following: CO4.4 CL1

a) Intel 8085 b) Intel 8086 c) Raspberry Pi d) RS9113

7 In IoT Building Blocks, routing and proper utilization of the processed data is the CO4.5 CL1
responsibility of ________

a) Sensors b) µController c) Gateways d) network layer

8 An integrated development environment (IDE) consists of________. CO4.6 CL1

 a) Source code editor b) Local build automation c) Debugger d) all the three

9 Arduino Uno has______ pins CO4.6 CL1

a) 14 i/p b) 14 o/p c) 40 i/o d) 14 i/o

10 In Arduino, writing codes for IDE programming is done in________language. CO4.6 CL1

a) Python b) Java c) C/C++ d) JavaScript

11 What is the microcontroller used in Arduino UNO? CO4.6 CL1

a) ATmega328p b) ATmega2560 c) ATmega32114 d) AT91SAM3x8E
12 A program written with the IDE for Arduino is called ______ CO4.6 CL1
a) IDE source b) Sketch c) Cryptography d) Source code
13 What is the full form of IDE in Arduino IDE IoT software? CO4.6 CL1
a) Intra Defence Environment b) Intra Development Environment
c) Integrated Development Environment d) Integrated Deployed Environment
14 Which of the following is not related to Arduino IDE IoT software? CO4.6 CL1
a) Serial monitor b) Verify c) Upload d) Terminate
15 Which library is used to access I2C in Arduino IoT devices? CO4.6 CL1
a) EEPROM b) Wire c) DHT11 d) ArduinoJson
16 How many digital pins are there on the UNO board? CO4.6 CL1
a) 14 b) 12 c) 16 d) 20
17 Which of the following is not a feature of the Raspberry PI model B IoT device? CO4.7 CL1
a) It has 256 MB SDRAM b) It has a single USB connector
c) It has its own operating system d) It has an Ethernet port
18 Raspberry Pi is a very cheap computer that runs on _______. CO4.7 CL1
a) Linux b) Windows c) Android d) iOS
19 In Raspberry Pi, Operating system is stored in _______ . CO4.7 CL1
a) HD cards b) SD cards c) Permanent memory d) hard disk
20 The number of USB ports available in Raspberry Pi is CO4.7 CL1
 a) one b) two c) three d) nil
21 Raspberry has 5 status LEDs. Among them, ‘LNK’ LED indicates _______. CO4.8 CL1
a)Power supply ON b) Alarm ON c) Link/Network activity d) SD card access
22 Raspberry pi SPI interface MISO refers to ________ CO4.8 CL1
a) Master In Slave Out b) Master Out Slave In
c) Slave Out Master In d) None of the above
23 ______ and ______ are main components of raspberry pi. CO4.8 CL1
a) LED, USB b) USB, HDMI c) LED, HDMI d) USB, POWER
24 Raspbian is ______ CO4.8 CL1
a) Assembler b) Language c) Compiler d) OS
25 Which of the following processor is used in the Raspberry PI 3 IoT device? CO4.8 CL1
a) Broadcom BCM2711 b) Broadcom BCM2837
c) Broadcom BCM2838 d) Intel 8085
 PART- B

4 Marks

1 Make use of smart IoT-based home automation system, demonstrates the key steps involved
in IoT Design Methodology.CO4.1 CL2 pgno: 114

Answer:

2 Analyse the embedded computing logic with respect to computer hardware and use of
microcontroller in embedded system with neat diagram. CO4.2 CL4

Answer:
3 While selecting a µController for your IoT application, few characteristics are important.
Justify them from your point of view CO4.3 CL2

Answer:

4 Outline the figure depicts one such IoT System on Chip model no.RS9113 ,which has been
designed and developed by redpine signals recently.CO4.4 CL2

Answer:

5 “A ‘Thing’ in IoT can be any object that has a unique identifier and which can send/receive
data over a network”- justify the statement by providing real-world examples. CO4.5 CL2
 Answer:

6 On what basis, basic building blocks of an IoT device classifies the number of modules which
is based on functional attributes.CO4.5 CL2

Answer:

Functional Attributes:
7 While uploading the program to your board, demonstrates the function of each symbol
appearing in the arduino IDE toolbar .CO4.6 CL2

Answer:

8 “Raspberry Pi runs various flavours of Linux and can perform almost all tasks that a normal
desktop computer can do”-Explain this statement by providing various flavours of linux.
CO4.7 CL4 pgno: 181

Answer:

Raspberry pi supports various flavors of linux including:

9 Utilize the Raspberry Pi frequently used commands which is more convenient to access the
device with a VNC connection or SSH.CO4.7 CL3 pgno: 185

Answer:

10 Compare the key metrics for choosing the best board with explaining the contrast between
arduino vs raspberry pi for IoT.CO4.8 CL4
 Answer:

S.I.NO Arduino Raspberry Pi

1 In the year 2005, the classrooms of the In the year 2012, Eben Upton first
Interactive Design Institute in Ivrea, introduced the Raspberry Pi device in
Italy, first introduced the Arduino February.
board.

2 Control unit of the Arduino is from the The control unit of Raspberry Pi is from
Atmega family. the ARM family.
3 While Raspberry Pi is based on a
Arduino is based on a microcontroller.
microprocessor.
4 While Raspberry Pi computes data and
It is designed to control the electrical
produces valuable outputs, and controls
components connected to the circuit
components in a system based on the
board in a system.
outcome of its computation.
5 While Raspberry Pi boards have a
Arduino boards have a simple hardware
complex architecture of hardware and
and software structure.
software.
6 CPU architecture: 8 bit. CPU architecture: 64 bit.
7 While Raspberry Pi requires more RAM,
It uses very little RAM, 2 kB.
1 GB.
8 While Raspberry Pi clocks a processing
It clocks a processing speed of 16 MHz.
speed of 1.4 GHz.
9 It is cheaper in cost. While Raspberry Pi is expensive.
10 It has a higher I/O current drive While Raspberry Pi has a lower I/O
strength. current drive strength.
11 With a neat diagram show the raspberry pi GPIO headers and explain the interfaces for
transferring the data in the board. CO4.8 CL3
 Answer:

12 Write a python program for controlling an LED with a switch where the condition is i) LED
is connected to GPIO pin 18 ii) switch is connected to pin 25. CO4.8 CL4 pgno: 188

Answer:
 PART - C
12 Marks
1 With a neat sketch IoT, analyze the design for smart health care system and justify how privacy
and security is provided in your prototype. CO4.1 CL4 pgno: 115
Answer:
Explanation:
Steps- 3 marks
Diagram – 6 marks
Explanation for diagram – 3marks
2 While designing an IoT application, examine how System on Chip in IoT is designed by Redpine
signals and show various applications involved in it. CO4.3 CL4
Answer:
Diagram – 5 marks
Explanation – 4 marks
Applications- 3 marks

3 Point out some examples that define IoT devices and outline the figure that shows a generic block
diagram of a single-board computer (SBC). CO4.4 CL3
Answer:
Explanation – 6 marks
Diagram – 6 marks
4 Examine the process of using the Integrated Development Environment (IDE) to prepare an
arduino board with neat presentation. CO4.6 CL4
Answer:
Explanation- 5 marks
Diagram – 7 marks

5 Articulate the special functions involved in designing the basic arduino board and explain the
procedure for installing and setting up of IDE. CO4.6 CL4
Answer:
Special functions – 3 marks
Explanation- 6 marks
Necessary diagrams – 3 marks

6 With a neat sketch, Analyse the various components or peripherals labelled in the Raspberry Pi
board by providing necessary examples CO4.7 CL3 pgno: 180
Answer:
Diagram – 6 marks
Explanation (various components) – 6 marks
7 Design an automatic lighting system with LDR for turning a light on/off based on the light-level
sensed in raspberry pi and write a python program to support the working of that design.CO4.8
CL6 pgno: 191
Answer:
Diagram- 6 marks
Explanation- 6 marks
8 Design an automatic refrigerator light system with LED for switching on/off from raspberry pi
and write a python program to support the working of that design.CO4.8 K6 pgno: 187
Answer:
Diagram – 6 marks
Program- 6 marks
 UNIT-5 / Case Studies and Real-world Applications
PART A (Objective Type - 1 Mark)

Real world design constraints - Applications - Asset management, Industrial automation,

smart grid, Commercial building automation, Smart cities - participatory sensing - Data
Analytics for IoT – Software & Management Tools for IoT Cloud Storage Models &
Communication APIs – Cloud for IoT - Amazon Web Services for IoT.

1 While designing a real-world IoT system, we need to consider few constraints. One of CO5.1 CL1
the following NOT belongs to the list of constraints. Identify it.

a) Technical design constraints

b) Data representation and visualization
c) Interaction and remote control
d) a, b & c are not belonging to the list of constraints
2 In dealing with real-world constraints, Power has major impact on the _____ of the CO5.1 CL1
application.
a) functionality b) serviceability c) longevity d) none of the above
3 Out of these, which are the applications of IOT? CO5.2 CL1
a) House b) virtual environment c) regional office d) all the above
4 In Industrial Automation, SOA refers to CO5.3 CL1

a) Secret Oriented Algorithm b) Secret Oriented Architecture

c) Service Oriented Algorithm d) Service Oriented Architecture

5 What is the role of Cloud in smart grid architecture of IoT? CO5.3 CL1

a) Store data b) Manage data c) Collect data d) Security

6 What is the example for smart grid edge device for utility? CO5.3 CL1

a) Smart Meters b) Smart Home c) Smart Car d) Smart College

7 What is the role of Sensor in smart grid architecture of IoT? CO5.3 CL1

a) Store data b) Manage data c) Collect data d) Security

8 The core element of architecture of smart city is CO5.3 CL1

a) Mobile Unified Service b) Urban Application Platform

c) Management center d) Integrated Information Provider

9 Identify the web technologies, which enable easy integration of device-level services CO5.3 CL1
with enterprise system.

a) DPWS b) REST c) Web Services (WS) d) all the three rulers

10 The goal of Participatory sensing is_______ CO5.4 CL1

a) Only collect data b) Allow people to access data

c) Share knowledge d) All of the above

11 In Participatory Sensing aspect, citizen’s major role is ______. CO5.4 CL1
a) Data Collector b) Collection System Operator
c) Analysis Provider d) None of the above
12 In Participatory Sensing, ________are fully empowered to contribute to the change that CO5.4 CL1
they would like to see in their living environment.

a) the rulers b) the authorities c) the citizens d) none of the above

13 The method by which companies analyse customer data or other types of information in CO5.5 CL1
an effort to identify patterns and discover relationships between different data elements
is often referred to as ______.

a) Customer data management b) Data mining

c) Data digging d) none of the above

14 Which one is simplest form of analytics? CO5.5 CL1

a) Predictive b) Descriptive c) All of the mentioned d) Prescriptive
15 Which language is preferred for IoT analytics? CO5.5 CL1
a) C++ b) Python c) HTML d) PHP
16 Cloud Models mainly relies on ________. CO5.6 CL1
a) Communication API b) data storage
c) one service to another d) storage memory
17 Xively cloud services are ______. CO5.7 CL1
a) XaaS b) IaaS c) PaaS d) NaaS
18 Xively automatically creates_______ to connect the device. CO5.7 CL1
a) API id & Feed Key b) Feed-id & API Key c) updates d)
downloads
19 Which of the following API allows the user to control electronic components? CO5.7 CL1
a) CoAP API b) MQTT API c) RESTful API d) Android API
20 In which year, AWS launched Machine Learning Speciality Certification? CO5.8 CL1
a) 2016 b) 2017 c) 2018 d) yet to launch
21 The difference between AWS and traditional IT models is _______. CO5.8 CL1
a) flexibility b) integrity c) trust-worthy d) no difference at all
22 AWS IAM stands for CO5.8 CL1
a) AWS Integrity Assessment Manual b) AWS Identity Access Management
c) AWS Internet Access Management d) none of the above
23 AWS EC2 refers to _____. CO5.8 CL1
a) Amazon Elastic Compute Cloud b) Amazon Energy Computing
c) AWS Energy Computing d) AWS Internet Computing
24 In AWS SQS, the queue acts as a_____ between the component producing and saving CO5.8 CL1
data, and the component receives the data for processing.
a) buffer b) control c) catalyst d) none of the above
25 Out of the following, mention the amazon web services for IoT. CO5.8 CL1
a) Amazon S8 b) Amazon Dynamo DB c) Amazon SQP d) Amazon EMH
 PART- B

4 Marks

1 From your learning point of view, categorize various applications of IoT related to our day-to-day
life. CO5.2 CL4

Answer:

Few Applications:

 Wearables
 Smart home applications
 Smart buildings
 Smart infrastructure
 Securities
 Health care
 Smart cities
 Industrial automation
 agriculture
2 Outline the figure with the processes of SOA paradigm from sensors and actuators used for
monitoring and control at shop-floor level up to enterprise system. CO5.3 CL2

Answer:
3 Company A wants to improve energy efficiency in their buildings and become green building
partner certified, which requires lowering their energy consumption by at least 25%. After
discussions with a building automation company, they have come to understand that this is a very
good investment that will quickly justify itself in terms of reduced energy cost. Analyse some of
the steps for reducing energy consumption to the scenario. CO5.3 CL4

Answer:

5 step plan:

1. Starts with data collecting from the buildings

2. Followed by analysis
3. Adjustments
4. Connecting the systems in the buildings to a local server
5. Finally connecting the buildings to a remote operations center.

4 For the following scenario, outline the figure which depicts the paradigm change from an
infrastructure delivering metering data for billing purposes toward a general-purpose monitoring
infrastructure that acts as an enable for a multitude of stakeholders and value-added services.
CO5.3 CL3

Answer:
5 Show the schematic representation of the framework that outlines seven domains for the smart
grid conceptual model which is defined by the National Institute of Standards and Technology.
CO5.3 CL3

Answer:

7 domains:
 Bulk Generation
 Transmission
 Distribution
 Customers
 Operations
 Markets
 Service providers

6 With a neat diagram, describe the use case that consists of three citizen journalists observe a fire
on the corner of Oak and Birch Street near Oak Park. Make use of participatory sensing activities
that focus on exploiting citizen journalist reports in order to produce richer information content
and potentially help others. CO5.4 CL3

Answer:
7 With a neat presentation, show an example of the data collected for forest fire detection where
each row in the table shows time stamped readings of temperature, humidity, light and CO
sensors. CO5.5 CL3 pgno: 337

Answer:

8 “While looking at the key concepts of WAMP, one of the concepts such as client and router shows
the communication between them by WAMP session”- justify the statement by outlining the
diagrammatic representation. CO5.6 CL2 pg.no:199

Answer:

WAMP Session between client and router:

9 Outline the diagram for the following scenario,” The client runs a WAMP application component
that publishes messages to the router. The router runs on the server and routes the messages to
the subscribers. The router decouples the publishers from the subscribers where the
communication happens over a WAMP- Web socket session. CO5.6 CL2 pgno: 200

Answer:

10 Infer the figure that shows a screenshot of i) how to create a new device from the xively dashboard
ii) creation of feed-id and API key.CO5.7 CL2

Answer:
11 Show the python program for stopping an EC2 instance. In this case, use the following function,
i) conn.get_all_instances ii) conn.stop_instances for getting information on all running and
stopping instances. CO5.8 CL3 pgno: 226

Answer:
12 Write a python code for uploading a file to amazon S3. Apply the following functions in your code
i) first establish the function by calling boto.connect_s3.ii) upload the files by
upload_to_s3_bucket_path function. CO5.8 CL4 pgno: 231

Answer:
 PART - C
12 Marks
1 Consider any use case example of smart applications of IoT, explain the architecture and
technology need in building the application. CO5.3 CL4
Answer:
Any example in smart application
Explanation- 6 marks
Diagram – 6 marks
2 In Industrial Automation, distinguish the various levels through SOCRADES Integration
architecture CO5.3 CL4
Answer:
Explanation – 5 marks
Diagram- 7 marks
3 Analyse how energy could be better managed in order to increase efficiency, without noticeably
impacting quality of life on the integration of smart house and its appliances to the smart grid.
CO5.3 CL4
Answer:
Explanation – 6 marks
Diagram – 6 marks

4 Appraise the importance of Participatory sensing process and infer some example in connection
with smart city implementation. CO5.4 CL5
Answer:
Explanation – 4 marks
Diagrams- 8 marks
5 Outline the deployment design of a forest fire detection system with multiple nodes which are
deployed in a forest and also show an example of the data collection.CO5.5 CL3 pgno: 336
Answer:
Explanation – 4 marks
Diagrams:
Deployment design – 4 marks
Data collection example- 4 marks
6 Analyse the distributed application architectures where the application components are
distributed on multiple nodes and communicate with messaging patterns provided by WAMP.
CO5.6 CL4 pgno: 198
Answer:
Explanation – 7 marks
Diagram- 5 marks
7 Consider an example of using xively cloud for an IoT system that monitors temperature and sends
the measurements to a xively channel. Write a python program for the above scenario where xively
python library must used.CO5.7 CL4 pgno: 205
Answer:
Program – 8 marks
Explanation – 4 marks
8 Make use of the purpose of Amazon Web service for IoT. Write a python program for the following
services i) launching an EC2 instance ii) creation of DynamoDB table. CO5.8 CL3 pgno: 225,234
Answer:
i) Amazon EC2 – 6 marks
ii) Amazon DynamoDB – 6 marks