Requirements Negotiation Tools

CSE5/7316LiGuo Huang

2

Pervasiveness of Software• Software-intensive systems prevalent across

industries/domains – E.g.: automotive, finance, consumer electronics, medical devices

etc.,• Information systems:

– Collects, stores, transforms, transmits, and/or processes information or data

– Goal: Provide information at right place/time– Ex.: Accounting system

• Embedded software-intensive systems:– Software only ONE (important) part of overall system– Often closely integrated with hardware– Ex.: Anti-lock braking system of a car

3

Challenges in Software Development• Software-based innovations

– Customers demanding innovative features software is key for realizing innovation

• Increasing Complexity– Greater number of functions realized by software increasing

complexity i.e., increased integration with external systems, customizability etc.,

• Higher quality demands– Pervasiveness of software higher level of quality

• Shorter development times– Increasing competition faster time to market

• Pressure to reduce costs– Increasing market pressure software systems must be developed at

lower costs

4

Project Success Rate

2000 2002 2004 2006 20080

10

20

30

40

50

60

4951

53

4644

23

1518 19

24

28

34

29

3532

2010 Standish Group CHAOS Summary Report

ChallengedFailedSucceded

Challenged: Over budget/schedule or undelivered projectsFailed: Cancelled projects

5

Lack of Stakeholder involvement and convergence viewed as major causes of project failure

1. User Involvement2. Executive Support3. Clear Business Objectives4. Emotional Maturity5. Scope Optimization6. Agile Process7. Project Management Expertise8. Skilled Resources9. Execution Capability10.Tools and Infrastructure

CHAOS ’10 – Factors Influencing Project Success

7

Why Is RE Important?• Flawed requirements a major cause of project

failure • Fixing an error in later phases 10x more

expensive• Incorrect requirements ↔ Incorrect system leads

to wasted costs• System maybe unreliable for practical use

disrupting normal day-to-day operations• The primary vehicle for going from “vision” to

“realization”

8

RE and the Enterprise

Requirements Engineering

Marketing

Customer Relationship Management

Product Management

Product roadmap/ strategy, key

requirements

New and revised

requirements

Customer wishes, Reported problems

Realized changes and

enhancements

Market needs and trends,Price range

New Features

9

RE and Software Development

Requirements Engineering

Project Management

System Maintenance

Quality Assurance

Requests for clarification and

improvement

Requirement Artifacts Change requests

Status of change requests

Project plan, Approved goals

Requirements & constraints Design &

Development

Solutions, New technologies

Monitoring data, Elicited goals

10

Types of Requirements• Functional Requirements: specify the functionality the system

shall provide to its users– Ex.: The system shall allow the users to access their profile page after

they provide valid credentials• Quality Requirements (a.k.a., Levels of Service): define the quality

properties of the entire system or of a system component, service or function– Ex.: Reliability, performance under high loads etc.,– “-ilities”: Availability, flexibility, scalability, usability, robustness,

interoperability etc.,• Constraints: Organization or technological requirement that

restricts a way in which the system shall be developed– Ex.: Legal constraints (Sarbanes-Oxley), Project/Budget/ Schedule

constraints, Physical constraints etc.,

11

Goal of RE: Establishing a Vision in Context

• Requirements Engineering processes start with an aim to change current reality

• Vision: (a.k.a “system vision”)– Essence of desired change defined briefly and

precisely– Describes overall goal(s) of the system– Usually associated with particular point in time of

when the vision should be realized– Serves as a guide during development for all Success

Critical Stakeholders (SCS) involved in the project

12

Goal of RE: Establishing a Vision in Context

• Each system is embedded within a given context

• Context (a.k.a. “system context”): Part of the system environment relevant for– Defining, understanding & interpreting system

requirements

13

Visualizing “Vision” in “Context”

Vision defines focus

• Establish system vision within existing system context• Deal with parts of the real world that are relevant and

their relation to the development context

14

Framework For RE

System Context

Core Activities

Requirements Artifacts

Valid

ation

Man

agem

ent

15

Framework For RE

System Context

Subject FacetMaintain

information about objects/events in

the real world.

Usage Facet Desired workflows,

usage goals, different user

groups, interaction models, laws & standards etc.,

IT System FacetExisting hardware,

software, communication

networks, peripheral devices

etc.,

Development FacetProcess guidelines

and constraints, QA methods, maturity

models, development

environments etc.,

16

Relationship Between Facets

Subject Facet

Representation

PresentationApplication

Usage Facet Development Facet

IT System Facet

RE happens here!!

17

Three Dimensions & Goals of Requirements Engineering

• Content:All relevant requirements are explicitly known and understood at the required level of detail

• Agreement:A sufficient agreement about the system requirements is achieved between the success critical stakeholders

• Documentation:All requirements are documented and specified in compliance with the relevant documentation/specification formats & rules

18

Visualizing The “Three Dimensions” Content

Documentation

Agreement

complete

vague

informal compliant with rules

individual views

consolidated views

Goal

19

Framework For RE

Core Activities

Documentation Document & specify elicited requirements as per defined

documentation and specification rules. Also

capture rationale and other relevant information

Elicitation

Negotiation1.Detect conflicts and make them explicit2. Resolve identified conflicts

20

Framework For RE

Elicitation

Identifying Requirement Sources

StakeholdersExisting Documentation

Existing System(s)Elicit Existing Requirements

Elicit already “known” requirements from relevant

sources

Developing new & innovative requirements

Typically not elicit-able and require collaborative and

creative processes

21

Techniques For Elicitation• Interviews• Workshops• Focus Groups• Observation of stakeholders/users etc.,• Questionnaires • Perspective-based readingUsually supported by “Assistance Techniques”– Brainstorming– Prototyping– Mind Mapping– KJ Analysis/Method– Elicitation Checklists

22

Framework For RE

Goals Stakeholder intention with

regard to the objectives, properties or use of the

system

ScenariosPositive/Negative,

Misuse,Exploratory,

Current-state/desired state,Main, alternative or exception

Solution oriented requirementsData Model,

Functional Model,Behavioral Model

Requirements Artifacts(Documented Requirements)

23

Framework For RE• Validation of context consideration

Check whether all relevant aspects in 4 contexts have been elicited, documented within the RE process

• Validation of execution of activitiesCheck adherence of activities to process, standards, guidelines etc.

• Validation of requirement artifactsCheck documented requirements w.r.t. content, documentation and agreements

Valid

ation

24

Validation Techniques• Inspections• Walkthroughs• Desk-checking (checking programs with

pen-paper)• PrototypingAbove are usually assisted by:• Validation checklists• Perspective-based reading• Verbalization of models• Creation of artifacts

25

Framework For RE• Observation of system context

Identification and management of context changes• Management of RE activities

Monitoring, controlling and adjustment of planned workflow of elicitation, documentation, negotiation and validation activities – standard project management

• Management of requirements artifacts– Establishing traceability between different artifacts– Prioritizing requirements– Managing changes via change management processes

Man

agem

ent

26

RE Framework == VBSE 4+1

• RE Framework advocated by Klaus Pohl is, in essence, isomorphic to VBSE’s 4+1

• VBSE brings value considerations to the foreground; RE Framework doesn’t seem to make it explicit

• Each of the ‘steps’ of the RE framework is traceable in VBSE’s 4+1 structure (and vice versa)

27

Theory-WCustomer

Developer

STOP THIS MADNESS!

Think of requirements as stakeholder negotiated win

conditions!!

As a team discuss what will make each of you “win”

(a.k.a. win conditions)

Identify any issues and come up with options to resolve them

Reach a mutual consensus and move

forward (WinWin Equilibrium)

Dr. Boehm

28

VBSE 4+1 • Theory W -“which values are important?”

and “how is success assured?” for a given software engineering enterprise.

• Utility theory (how important are the values?)• Decision theory (how do stakeholders’ values

determine decisions?)• Dependency theory (how do dependencies

affect value realization?) • Control theory (how to adapt to change and

control value realization?).

29

VBSE 4+1

30

VBSE 4+1

31

WinWin Negotiation tools Evolution• The first generation of WinWin requirements negotiation

support system was developed at USC in 1994• Easy WinWin: is the fourth generation implementation for the

WinWin requirements negotiation approach based on a Group Support System

• Wiki WinWin: The WikiWinWin approach includes a stakeholder collaboration process and corresponding support tools. The WikiWinWin creates a sequence of steps and instructions to guide the stakeholders working out mutually satisfactory requirements.

• Winbook: A Social Networking Based Framework for Collaborative Requirements Elicitation and WinWin Negotiations

32

WinWin Negotiation tools Evolution• What is EasyWinWin?• EasyWinWin is a requirements definition methodology that builds on the

win-win negotiation approach and leverages collaborative technology to improve the involvement and interaction of key stakeholders. With EasyWinWin, stakeholders move through a step-by-step win-win negotiation where they collect, elaborate, and prioritize their requirements, and surface and resolve issues to come up with mutually satisfactory agreements

• The WinWin negotiation model defines 4 types of artifacts – Win Condition, Issue, Option, and Agreement (WIOA)

33

WinWin Negotiation tools Evolution Activities• Review and expand negotiation topics• Brainstorm stakeholder interests• Converge on Win Conditions:• Capture a glossary of Terms• Prioritize Win Conditions• Reveal Issues and Constraints• Identify Issues, Options• Negotiate Agreements

34

WinWin Negotiation tools Evolution• Review and expand negotiation topics

35

WinWin Negotiation tools Evolution• Brainstorm stakeholder interests

36

WinWin Negotiation tools Evolution• Converge on Win Conditions:

37

WinWin Negotiation tools Evolution• Prioritize Win Conditions• Reveal Issues and Constraints• Identify Issues, Options• Negotiate Agreements

38

Wiki WinWin• A wiki is actually two things: a program that makes it exceptionally easy

for people to edit web pages and a philosophy regarding how users should go about the editing of web pages

• A wiki has several key characteristics, which make it different from the other widely used collaborative technologies, e.g., discussion forums, weblogs, and GSS (group support systems)

• It uses simple syntax and conventions to allow users easy editing or organizing of web pages

• It enables web documents to be authored collectively without individual ownership of the document

• The wiki can preserve the revision history, allow new information to update, and overwrite the old version

• Wiki in general makes a basic assumption of the goodness of people. It allows content to be immediately published upon being saved. And it relies on the community of users to catch malicious content and correct it

39

Wiki WinWin• Many wiki engines are good in supporting collaboration activities e.g. the

popular MediaWiki and TWiki. The Wikipedia, built upon the MediaWiki wiki engine, is one of the most well known cases. It’s an online encyclopedia, collaboratively written by a group of about 50,000 volunteers.

• Yahoo uses TWiki internally to manage documentation and project planning; Disney uses TWiki as the central resource for ideas, notes, how to’s, specs, and brainstorming; and SAP uses TWiki for multi-team collaboration.

40

Wiki WinWin• The WikiWinWin• The WikiWinWin approach includes a stakeholder collaboration process

and corresponding support tools. The WikiWinWin creates a sequence of steps and instructions to guide the stakeholders working out mutually satisfactory requirements.

• Ease of use• Maintain the WIOAs• Guidance for negotiation process• Support of synchronous collaboration• Versioning across several pages

41

Wiki WinWin

42

Wiki WinWin

43

Wiki WinWin

44

WinbookTheory - W

Requirement Specifications

Putting It All Together

User Stories

Facebook Gmail

45

Winbook• A collaborative, social networking based tool

for requirements brainstorming similar to facebook…

• …with requirements organization using color-coded labels similar to Gmail…

• …to collaboratively converge on software system requirements reaching win-win equilibrium (based on Theory-W)…

• …by keeping it short and simple like XP’s user stories!

46

47

48

Tutorial• http://www.youtube.com/watch?v=xFUj9Gj5X

TU&feature=youtu.be