Week 6 _07_Software Requirements Document

1. Software Requirements Document

SOFTWARE
REQUIREMENTS
DOCUMENT
DR. CHANDRA REKA

2. OUTLINE

Software requirements document
◦ Preparation of the requirement document
◦ The outline of requirement document
◦ Matters needing attention for writing document
◦ Some examples

3. Learning Outcomes

At the end of this LESSON
you should be able to:
◦ Describe what is Software
Requirements Document
◦ Identify the outline/content
for documentation
◦ Explore various examples of
documentations

4. Software Requirements Document

https://dilbert.com/strip/1999-08-09
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5. Software Requirements Document

Specification
• A document that states requirements/needs (eg. of business,
stakeholder, system or software)
• Defines what client/purchaser will acquire and what supplier
is required to provide
• Used to:
Ensure supplier delivers according to the specification
Measure performance of supplier
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6. Importance of clear specifications

Control risks – product delivered according to requirements
Value for money – vendors able to evaluate and respond
Maximise success – accurate statement from acquirer/buyer
Reference – source of reference at later stage
Review – reviews possible at later stage
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7. Software Requirements Document

Audience?
Customers and users
Systems Analysts
Developers, Programmers
Testers
Project Managers
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8. Building the appropriate specification

Project 1: Small project, 1 programmer, 2 months work
Project 2: Large project, 50 programmers, 2 years work
Project 1
Project 2
Document
Programmer discusses with
customer then produces 2
page document
Team of analysts model the requirements,
then document in a 500-page Software
Requirements Specification (SRS)
Purpose of the
specification
Clarity in programmer’s
understanding
Feedback to customer
Built to document
Should contain enough detail for
programmers
Management view
Resources allocated
Specification is not relevant
Specifications used to estimate resources
Readers/Audience
Primary: Specification author
Secondary: Customer
Primary: programmers, testers, managers
Secondary: Customers
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9. Requirements Scope

Software Requirements
Specification (SRS)
Business Requirements
Specification (BRS)
Stakeholder
Requirements
Specification (StRS)
System Requirements
Specification (SyRS)
ISO/IEC/IEEE 29148:2018(E)(2018, pg. 19)
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10. Types of Requirements Document

ISO/IEC/IEEE 29148:2018(E)(2018) standards for requirements
engineering recommends the following documents:
• Business requirement specification (BRS)
• Stakeholder requirements specification (StRS)
• System requirements specification (SyRS)
• Software requirements specification (SRS), if adhering to
ISO/IEC/IEEE 12207* (may also be known as System/Software
Requirements Specification).
*Systems and software engineering — Software life cycle processes
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11.

12. Difference between BRS & FRS

The Business Requirement Specification (BRS) describes the high-
level business needs whereas the Functional Requirement Document
(FRD / FRS) outlines the functions required to fulfill the business
need.
BRS answers the question what the business wants to do whereas
the FRD gives an answer to how should it be done. FRD is derived
from a (Business Requirement Document) BRD.

13. Is there Really One Requirements document template that rules them all?

No. Different companies, and even departments within companies,
use different requirements documentation templates – dependent on
their specific internal and external stakeholders, technology and
systems involved, and a host of other factors.
And Yes. Whatever the template, a core set of key information is
contained in each. And whatever the methodology or terminology
being used, this information set remains central to any Requirements
template.
Any form of documentation that helps you gain agreement among the
team about the scope for a project, and supports information requests
from other internal, external stakeholders, is good enough as a
Requirements template.

14. BREAK

15. Requirements Document and Processes

Each requirement document documents the following
requirement processes:
• Business or mission analysis process
• Stakeholder needs and requirements definition process
• Systems requirements definition process or system/software
requirements definition process
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16. Requirements Document – Content

Software requirements documents should contain the following:
a. Identification
• Title
• Revision notice
b. Front matter
• Table of contents
• List of figures
• List of tables
Following sections describe the content of each type of requirements
document
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17. Business or Mission Analysis Process

ISO/IEC/IEEE 29148:2018(E)(2018, pg. 21)
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18. Business or Mission Analysis Process

ISO/IEC/IEEE 29148:2018(E)(2018, pg. 22)
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19. Business Requirements Specification (BRS) Document

“describes the organization’s motivation for why the system is being
developed or changed, defines processes and policies/rules under
which the system is used and documents the top-level requirements
from the stakeholder perspective including expressing needs of
users/operators/maintainers as derived from the context of use in a
specific, precise and unambiguous manner”
ISO/IEC/IEEE 29148:2018(E)(2018)
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20. Business Requirements Specification (BRS) Document

• how the organization is pursuing new business or changing the
current business in order to fit a new business environment
• how to utilize the (new) system as a means to contribute to the
business
• specified by the business
• business management level lead and participate in BRS
• includes organizational requirements and business
requirements
• typically combined with Stakeholder Requirements
Specification (StRS)
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21. Business Requirements Specification (BRS) Document - Outline

1. Introduction
1.1 Business purpose
1.2 Business scope
1.3 Business overview
1.4 Definitions
1.5 Major stakeholders
2. References
3. Business Management Requirements
3.1 Business environment
3.2 Mission, goals and objectives
3.3 Business model
3.4 Information environment
5. Preliminary operational concept of proposed
system
5.1 Preliminary operational concept
5.2 Preliminary operational scenarios
6. Other preliminary life-cycle concepts
6.1 Preliminary acquisition concept
6.2 Preliminary deployment concept
6.3 Preliminary support concept
6.4 Preliminary retirement concept
7. Project Constraints
8. Appendix
8.1 Acronyms and abbreviations
4. Business Operational Requirements
4.1 Business processes
4.2 Business operational policies and rules
4.3 Business operational constraints
4.4 Business operational modes
4.5 Business operational quality
4.6 Business structure
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22. Business Requirements Specification (BRS) Document

1. Introduction
1.1 Business
purpose
1.2 Business scope
1.3 Business
overview
1.4 Definitions
1.5 Major
stakeholders
1.1 Business purpose
• reason and background for which the
organization is pursuing new business
or changing the current business in
order to fit a new management
environment
1.2 Business scope
• identify business domain
• define range of business activities
• describe scope of system being developed or
changed
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23. Business Requirements Specification (BRS) Document

1. Introduction
1.1 Business purpose
1.3 Business overview
1.2 Business scope
1.3 Business overview
• relationship between internal divisions
1.4 Definitions
and external entities
1.5 Major stakeholders
• diagram recommended
1.4 Definitions
• define words or phrases with special meaning
1.5 Major stakeholders
• list stakeholders
• describe how they will influence the
organization and business
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24. Business Requirements Specification (BRS) Document

2. References
2. References
• list of referenced documents
• identify documents by date, report number,
title, publishing organization
• specify sources
• organize by “Compliance” section and
“Guidance” section
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25. Business Requirements Specification (BRS) Document

3. Business
Management
3. Business Management Requirements
Requirements
3.1 Business environment
3.1 Business
• external and internal factors to understand
environment
new or existing business
3.2 Mission,
• elicit stakeholder requirements
goals and
• influences to business eg. market trends,
objectives
3.3 Business
laws and regulations, social responsibilities,
model
technology base
3.4 Information
environment
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26. Business Requirements Specification (BRS) Document

3. Business Management Requirements
3.2 Mission, goals and objectives
• business results to be obtained
3.3 Business model
• methods for business mission to be
achieved
3.4 Information environment
• strategy for organization decision
- project portfolio
- long term system plan
- database configuration
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3. Business
Management
Requirements
3.1 Business
environment
3.2 Mission, goals
and objectives
3.3 Business model
3.4 Information
environment
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27. Business Requirements Specification (BRS) Document

4. Business
4. Business Operational Requirements
Operational
Requirements
4.1 Business processes
4.1 Business
• procedures of business activities
processes
4.2 Business
and possible system interfaces
operational policies
4.2 Business operational policies and
and rules
rules
4.3 Business
operational
• logical propositions for conducting the business
constraints
processes
4.4 Business
operational modes
4.3 Business operational constraints
4.5 Business
• conditions to be imposed in conducting the
operational quality
business process
4.6 Business
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structure

28. Business Requirements Specification (BRS) Document

4. Business Operational
Requirements
4.1 Business processes
4.2 Business
4. Business Operational Requirements operational policies
and rules
4.4 Business operational modes
4.3 Business
• methods to conduct the business
operational constraints
operation in an unsteady state
4.4 Business
4.5 Business operational quality
operational modes
• level of quality required for the 4.5 Business
operational quality
business operation
4.6 Business structure
4.6 Business structure
• structures in the business relevant to the system
• eg. organization, role and responsibility, geographic,
resource sharing
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29. Business Requirements Specification (BRS) Document

5. Preliminary operational concept of
proposed system
5.1 Preliminary operational concept
• describe proposed system in
high-level manner (no design)
• include:
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5. Preliminary operational
concept of proposed system
5.1 Preliminary operational
concept
5.2 Preliminary operational
scenarios
operational policies and constraints
description of the proposed system
modes of system operation
user classes and other involved personnel
support environment
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30. Business Requirements Specification (BRS) Document

5. Preliminary operational concept of 5. Preliminary operational
concept of proposed system
proposed system
5.1 Preliminary operational
5.2 Preliminary operational
concept
scenarios
5.2 Preliminary operational
• examples of how
scenarios
users/operators/
maintainers will interact with the
system in important contexts of
use
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31. Business Requirements Specification (BRS) Document

6. Other preliminary life-cycle concepts
6.1 Preliminary acquisition concept
• describe how system is to be acquired
6.2 Preliminary deployment concept
• describe how system is to be deployed
6.3 Preliminary support concept
• describe how system is to be
supported
6.4 Preliminary retirement concept
• describe how system is to be retired
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6. Other preliminary
life-cycle concepts
6.1 Preliminary
acquisition concept
6.2 Preliminary
deployment concept
6.3 Preliminary
support concept
6.4 Preliminary
retirement concept
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32. Business Requirements Specification (BRS) Document

7. Project Constraints
7. Project Constraints
• describe constraints to performing 8. Appendix
8.1 Acronyms and
the project within cost and schedule
abbreviations
8. Appendix
8.1 Acronyms and abbreviations
• spell out or define all acronyms and
• abbreviations used in the documents
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33. Business Requirements Specification (BRS) Document

An example
https://simplicable.com/new/business-requirements-document
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34. break

35. Stakeholder Needs and Requirements Definition Process

ISO/IEC/IEEE 29148:2018(E)(2018, pg. 26)
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36. Stakeholder Needs and Requirements Definition Process

ISO/IEC/IEEE 29148:2018(E)(2018, pg. 26)
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37. Stakeholder Requirements Specification Document (StRS)

“describes the organization’s motivation for why the system is being
developed or changed, defines processes and policies/rules under
which the system is used and documents the top-level requirements
from the stakeholders’ perspective including expressing needs of
users/operators/maintainers as derived from the context of use in a
specific, precise and unambiguous manner”
ISO/IEC/IEEE 29148:2018(E)(2018)
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38. Stakeholder Requirements Specification (StRS) Document

• how the organization will utilize the system as a means to
contribute to the business
• specified by stakeholders
• includes organizational requirements, business requirements
and user requirements
• stakeholder participates in the StRS
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39. Stakeholder Requirements Specification (StRS) Document - Outline

1. Introduction
1.1 Stakeholder purpose
1.2 Stakeholder scope
1.3 Overview
1.4 Definitions
1.5 Stakeholders
2. References
3. Business Management Requirements
3.1 Business environment
3.2 Mission, goals and objectives
3.3 Business model
3.4 Information environment
5. User requirements
6. Detailed life-cycle concepts of proposed system
6.1 Operational concept
6.2 Operational scenarios
6.3 Acquisition concept
6.4 Deployment concept
6.5 Support concept
6.6 Retirement concept
7. Project Constraints
8. Appendix
8.1 Acronyms and abbreviations
4. System Operational Requirements
4.1 System processes
4.2 System operational policies and rules
4.3 System operational constraints
4.4 System operational modes and states
4.5 System operational quality
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40. Stakeholder Requirements Specification (StRS) Document

1. Introduction
1. Introduction
1.1 Stakeholder purpose
1.1 Stakeholder
• reason and background for which the
purpose
organization is pursuing new business
1.2 Stakeholder scope
or changing the current business in
1.3 Overview
order to fit a new management
1.4 Definitions
1.5 Stakeholders
environment
1.2 Stakeholder scope
• identify business domain
• define range of business activities
• describe scope of system being developed or
40
changed
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41. Stakeholder Requirements Specification (StRS) Document

1. Introduction
1.1 Business purpose
1.2 Business scope
1.3 Overview
1.3 Overview
• relationship between internal divisions 1.4 Definitions
1.5 Stakeholders
and external entities
• diagram recommended
1.4 Definitions
• define words or phrases with special meaning
1.5 Stakeholders
• list stakeholders
• how they are related to the development and
operation of the system
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42. Stakeholder Requirements Specification (StRS) Document

2. References
2. References
• list of referenced documents
• identify documents by date, report number,
title, publishing organization
• specify sources
• organize by “Compliance” section and
“Guidance” section
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43. Stakeholder Requirements Specification (StRS) Document

3. Business Management Requirements
3. Business
3.1 Business environment
Management
• external and internal factors to understand Requirements
3.1 Business
new or existing business
environment
• elicit stakeholder requirements
3.2 Mission, goals
• influences to business eg. market trends,
objectives
laws and regulations, social responsibilities,
3.3 Business mode
technology base
3.4 Information
environment
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44. Stakeholder Requirements Specification (StRS) Document

3. Business
Management
Requirements
3. Business Management Requirements
3.1 Business
3.2 Mission, goals and objectives
environment
• business results to be obtained
3.2 Mission, goals and
3.3 Business model
objectives
• methods for business mission to be achieved
3.3 Business model
3.4 Information
3.4 Information environment
environment
• strategy for organization decision
- project portfolio
- long term system plan
- database configuration
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45. Stakeholder Requirements Specification (StRS) Document

4. System Operational
Requirements
4.1 System processes
4.2 System operational
policies and rules
4.3 System operational
constraints
4.4 System operational
modes and states
4.5 System operational
quality
4. System Operational Requirements
4.1 System processes
• how system supports business
activities
4.2 System operational policies and
rules
• how business operational policies and rules will
likely be addressed in functional requirements in
the SyRS and SRS
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46. Stakeholder Requirements Specification (StRS) Document

4. System Operational
Requirements
4.1 System processes
4.2 System operational policies
and rules
4.3 System operational constraints
4.4 System operational modes and
states
4.5 System operational quality
4. System Operational Requirements
4.3 System operational constraints
• system conditions and functional
requirements to be imposed on
the system in conducting the
business process
4.4 System operational modes and
states
• operational modes and states to support system operation
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47. Stakeholder Requirements Specification (StRS) Document

4. System Operational Requirements
4.5 System operational quality
• level of quality required for the
system operation
• eg. performance, compatibility,
reliability, security, maintainability
and portability
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4. System Operational
Requirements
4.1 System processes
4.2 System operational policies
and rules
4.3 System operational
constraints
4.4 System operational modes
and states
4.5 System operational quality
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48. Stakeholder Requirements Specification (StRS) Document

5. User requirements
• requirements for use that provide
the basis for design and
evaluation of systems to meet
identified user needs
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5. User requirements
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49. Stakeholder Requirements Specification (StRS) Document

6. Detailed life-cycle concepts of
proposed system
6.1 Operational concept
• describe proposed system in
high-level manner (no design)
• include:
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6. Detailed life-cycle concepts
of proposed system
6.1 Operational concept
6.2 Operational scenarios
6.3 Acquisition concept
6.4 Deployment concept
6.5 Support concept
6.6 Retirement concept
operational policies and constraints
description of the proposed system
modes of system operation
user classes and other involved personnel
support environment
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50. Stakeholder Requirements Specification (StRS) Document

6. Detailed life-cycle concepts of
proposed system
6.2 Operational scenarios
• examples of how users/operators/
maintainers will interact with the
system in important contexts of use
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6. Detailed life-cycle concepts of
proposed system
6.1 Operational concept
6.2 Operational scenarios
6.3 Acquisition concept
6.4 Deployment concept
6.5 Support concept
6.6 Retirement concept
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51. Stakeholder Requirements Specification (StRS) Document

6. Detailed life-cycle
concepts of proposed
system
6. Detailed life-cycle concepts of proposed
6.1 Operational
system
concept
6.3 Acquisition concept
6.2 Operational
• describe how system is to be acquired
scenarios
6.3 Acquisition
6.4 Deployment concept
concept
• describe how system is to be deployed
6.4 Deployment
6.5 Support concept
concept
• describe how system is to be supported
6.5 Support concept
6.6 Retirement concept
6.6 Retirement
• describe how system is to be retired
concept
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52. Stakeholder Requirements Specification (StRS) Document

7. Project Constraints
• describe constraints to performing
the project within cost and schedule
7. Project
Constraints
8. Appendix
8.1 Acronyms and
abbreviations
8. Appendix
8.1 Acronyms and abbreviations
• spell out or define all acronyms and abbreviations used in
the documents
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53. EXERCISE

Upload one example of BRS in MS Teams. Share with the class

54. Reference Materials

ISO/IEC/IEEE. (2018). Systems and software engineering — Life cycle processes —
Requirements engineering. ISO/IEC/IEEE 29148:2018(E).
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