5. Process and working structure

Question 1

Process

Answer 1

A set of interrelated activities performed in a given order to process information or materials

Question 2

The RE process

Answer 2

1. shapes the information flaw
2. communication model between participants
3. defines the RE work products to be used or produced
4. provides a framework in which RE elicit, document, validate and manage requirements

Question 3

Overall process fit

Answer 3

1. process might require wp that the RE process must deliver
2. terminology in the RE should be aligned

Question 4

Influencing factors

Answer 4

1. overall process fit
2. development context
3. stakeholder availability and capability (exploitative, continuous)
4. shared understanding (the more the more light weight)
5. complexity and criticality
6. constraints (customer or regulator)
7. time and budget available
8. validity of requirements (likely to change)
9. experience of requirements engineer

Question 5

Development context

Answer 5

1. customer-supplier-user relationship
2. development type
3. contract
4. trust

Question 6

Development type

Answer 6

1. a supplier specifies and develops a system for a specific customer
2. an organization develops a system with the intention to sell it as a product or service to many customers in a certain market segment
3. a supplier configures a system for a customer from a set of ready-made components
4. a vendor enhances and evolves an existing product

Question 7

Contract

Answer 7

1. is there a contract or similar agreement that formal defines deliverables, costs, deadlines, responsibilities …
2. fixed or iterative functionality …

Question 8

Process facets

Answer 8

1. custom-specific vs market oriented (development type)
2. prescriptive vs exploratory (deals with purpose and role of requirements)
3. linear vs iterative

Question 9

Linear RE process

Answer 9

1. requirements are specified up front in a single phase
2. mostly heavyweight
3. produce comprehensive requirements specification that requires no or only little adaptation or few changes during the design and implementation of the system

Question 10

Criteria for choosing a linear RE process

Answer 10

1. Dev process is plan driven and linear
2. Stakeholders are available, know their requirements and can specify them up front
3. a comprehensive requirements is required as a contractural basis for outsourcing or tendering the design and implementation of the system
4. regulatory authorities require a comprehensive formally released requirements specification at an early stage of the development

Question 11

An iterative RE process

Answer 11

1. specified incrementally starting from initial goals
2. interwine the specification of the requirements with the design and implementation of the system
3. lightweight process

Question 12

Criteria for choosing an iterative RE process

Answer 12

1. Dev process is iterative and agile
2. many requirements are not known up front but will emerge and evolve during the development of the system
3. stakeholders are available such that short feedback loops can be established as a means of mitigating the risk of developing the wrong system
4. the duration of development allows more than one iteration
5. ability to change requirements easy is important

Question 13

Prescriptive

Answer 13

1. requirements constitute a contract: all requirements are binding and must be implemented.
2. create a requirements specification that can be implemented with no or little interaction between stakeholder and developer

Question 14

Explorative RE

Answer 14

1. goals are not know a priory, concrete requirement have to be elicited => have to be explored

Question 15

Criteria for choosing a prescriptive RE process

Answer 15

1. customer requires a fixed contract for system development, often with fixed functionality, scope, price and deadline
2. functionality and scope take precedence over cost and deadlines
3. development of the specified system may be tender or outsourced

Question 16

Criteria for choosing an explorative RE process

Answer 16

1. Stakeholder initially have only a vague idea about their requirements
2. Stakeholders are strongly involved and provide continuous feedback
3. deadlines and cost take precedence over functionality and scope
4. the customer is satisfied with a framework contract about goals, resources and the price to be paid for a given period of time or number of iterations
5. It is not clear a priori which requirements shall actually be implemented and in which order they will be implemented

Question 17

Customer specific RE process

Answer 17

1. system is ordered by a customer and developer by a supplier for his customer
2. supplier and customer might be part of same organisation

Question 18

Market oriented RE process

Answer 18

the system is developed as a product or a service for a market, targeting specific user segments.

the organisation that develops the system also drives the RE process

Question 19

Criteria for choosing a customer-specific RE process

Answer 19

1. the system will be used mainly by the organisation that has ordered the system and pays for its development
2. important stakeholders are mainly associated with the customer’s organisation
3. the customer wants a requirements specification that can serve As a contract

Question 20

Criteria for choosing a market oriented RE process

Answer 20

1. the developing organization or one of its clients intends to sell the system as a product or service
2. prospective users are not individually identifiable
3. the RE have to design the requirements so that they match the envisaged needs of the targeted users
4. Product owners, marketing people, digital designers, system architect are primary stakeholders.

Question 21

Mutual influence of facets

Answer 21

1. linear and prescriptive are frequently chosen together
2. explorative & iterative
3. market oriented does not combine well with prescriptive and linear

Question 22

Agile setting best process

Answer 22

iterative and explorative

Question 23

Prerequisite for using linear RE process

Answer 23

1. sophisticated process for changing requirements is in place
2. feedback loops are long - need intense validation

Question 24

Three common facet combinations

Answer 24

1. Participatory RE process: iterative & explorative & customer-specific
2. Contractual RE process: linear & prescriptive & customer specific
3. Product-oriented: iterative&explorative&market oriented

Question 25

Five step procedure to configure an RE process

Answer 25

1. Analyse influencing factors 2. Asses facet criteria 3. Configure 4. Determine work products (aligned with the dev process) 5. Select appropriate practices

Question 26

Participatory RE process

Answer 26

1. iterative & explorative & customer-specific 2. supplier and customer collaborate closely, stakeholders are strongly involved in both the RE and dev process 3. fits the agile process 4. WPs: product backlog, user stories and task descriptions, vision, prototypes

Question 27

Contractual RE process

Answer 27

1. linear & prescriptive & customer specific 2. development is tendered or outsourced to a provider with a contract based on comprehensive requirements specification 2. requirements are a contractual basis for ppl not involved in the specification and with little stakeholder interaction after requirements phase

Question 28

Product oriented RE process

Answer 28

1. iterative & explorative & market oriented 2. organization is developing a system as a product for the market