Lecture 2

Question 1

Definitions for requirements enginnering?

Answer 1

1. Alan Davis - ‘All activities up to but not inlcuding the decompisition of software into its actual architectual components’ (1988)(
2. Bray - ‘An investigation and description of the problem domain and requirements. Followed by the design and documentation of the characteristics for a solution system that will meet those requirements’.

Question 2

Why is requirements engineering so important?

Answer 2

• Provides the foundation upon which the rest of the project is built
• Inaccuracies, errors and omissions during this stage can result in problems which may increase cost and duration of the project.

Question 3

What is the problem domain?

Answer 3

‘A part of the universe within which the problem exists (The area of the project which we gather information in order to fully comprehend the tasks or problem at hand)
- A problem domain can be regarded as a set of subsystems, known as terminators, which will interface with the new proposed solution system.

Question 4

Solution system

Answer 4

The system that will be built to solve the problems within the problem domain (application or product)
- The problem domain and solution system are interfaced by the system specification

Question 5

What is requirements?

Answer 5

1. Bray - ‘Requirements are the effects that the client wishes to be brought about in the problem domain’
2. ‘A condition or capability that must be met by the system to solve a problem or achieve an objective’

Question 6

What is needed in the project?

Step by step and small description of each

Answer 6

1. Fundamental requirements - Describe the functionality/ everything the system does
2. Performance Requirements - Parameters of functionality (Speed - Throughput or response times; Capacity - Storage, number of operations performing concurrently; Reliability - Mean time between failure and an indication of system availability; Usability - Operation availability)
3. Design constraints - Non functional requirements that affect how the system is built but not what the system does; anything that the client is telling you must be on the system design (brandning, logo)
4. Commerical constraints - Costs and project time scales; essential to show the cost of the project as well as profit in the report but not in delivery to client.

Question 7

General problem domain entities?

Answer 7

1. Interviews - With key stakeholders, customers, managers, employees etc
2. Questionares - Mainly for widespread gathering of customer information
3. Background reading - Good to have a base knowledge of the company, how they operate and why and their market and product aswell as their current system.
4. Comparable systems - Systems already in the market leading to a comprehensive understanding of features and key functionality
5. Legislation - Database records and ensuring that the correct legislation is in place to store client and customer information aswell as access levels; How to gain ownership/ follow legislation and why it is important (GDPR and Accessibility act)
6. Financial - Cost of these information gathering techniques, mockups of the system; an interview with key stakeholders will identify and outline costs and overall financial expectations.