Module 11: Embedded Systems

Question 1

List 4 requirements for embedded systems that differ from the requirements for general purpose computers. Explain two of these in more detail, using examples to illustrate your points.

Answer 1

Reduced system footprint (fewer chips and smaller size)

Low power consumption

Resistance to electromagnetic noise

Robustness (can handle heat, vibration, and shock)

results: lower power consumption and real time response

Question 2

Briefly explain the difference between transformational systems and reactive systems

Answer 2

Transformational Systems:
Have all inputs available at the start, perform a computation, and then produce outputs. They eventually finish execution.
- Example: A payroll program that reads employee data, calculates wages, and outputs payslips.

Reactive Systems:
Continuously interact with their environment, responding to unpredictable external events. They don’t have a defined end.
- Example: A temperature control system that constantly monitors and adjusts the air conditioner based on sensor input.

Question 3

Explain what is meant by real-time embedded systems. Give an example of an application that would require real-time embedded systems

Answer 3

A real-time embedded system is one that must respond to input or environmental changes within a specific, guaranteed time limit. Failure to do so is considered a system failure.

Example: Aircraft control systems, power grid monitoring, or medical devices (like pacemakers) — these require immediate responses to ensure safety and reliability

Question 4

Briefly explain what is meant by Internet of Things. Give two examples of how
embedded systems are used in applications using IoT

Answer 4

The Internet of Things (IoT) is a system of computing devices connected via the Internet, consisting of sensors, actuators, and embedded systems that exchange data.

Examples of embedded systems in IoT applications:

1. Smart home devices — e.g., embedded controllers in air-conditioners or ovens that can be controlled remotely by a smartphone.
2. Smart buildings — embedded sensors adjust lighting and temperature based on occupancy or time of day.

Question 5

Explain the function of a data centre, and some of the services provided by a typical data centre

Answer 5

A data centre is a physical facility used to house critical computing equipment and data.

Functions and services include:

• Hosting servers, storage, routers, and networking equipment.
• Providing high-speed Internet connections.
• Maintaining stable power supply (with backups).
• Ensuring temperature control (cooling systems).
• Providing physical and virtual security for data.
• Safety systems such as fire suppression and backup equipment.

Question 6

Briefly describe the concept of cloud computing and the main advantages of cloud computing over traditional IT infrastructure deployment

Answer 6

Concept:
Cloud computing is the on-demand delivery of computing resources over the Internet. It follows a pay-as-you-use model, similar to utilities like electricity or water.

Advantages over traditional IT infrastructure:

Cost efficiency: No need for companies to buy or maintain physical hardware.

Scalability: Resources can be increased or reduced based on demand.

Accessibility: Applications and data are accessible from anywhere with Internet.

Reduced maintenance: Updates, patches, and backups are handled by the provider.

Question 7

Explain what is meant by each of the following, giving examples for each:
a. IaaS
b. PaaS
c. SaaS
d. Other XaaS components

Answer 7

a.
IaaS – Infrastructure as a Service
Provides virtualised computing resources such as servers, storage, and networking over the Internet.

Example: Amazon Web Services (AWS EC2), Rackspace.

Users rent infrastructure rather than owning it.

b.
PaaS – Platform as a Service
Provides tools and software for developers to build, test, and deploy applications. Includes middleware, databases, and operating systems.
Example: Google App Engine, Microsoft Azure.

Developers focus on building applications, not managing hardware.

c.
SaaS – Software as a Service
Delivers applications via a browser or app, with no local installation required. The provider handles maintenance and updates.

Example: Office 365, Google Workspace, Salesforce.

Advantages: automatic updates, easy scalability, accessible anywhere.

d.
Other XaaS Components
Additional “as a Service” models include:

DBaaS: Database as a Service (cloud-hosted databases).

Storage as a Service: Cloud file storage (e.g., Google Drive).

DaaS: Desktop as a Service.

CaaS: Communications as a Service (e.g., cloud telephony).

DRaaS: Disaster Recovery as a Service.

AIaaS: Artificial Intelligence as a Service.

MaaS: Malware as a Service (security service to prevent attacks).