CHAP 9 (REQUIREMENTS VALIDATION AND NEGOTIATION)

RISK NON VALID REQUIREMENT

Subsequent errors in planning, architecture, design, test, implementation

Conflicts are not resolved.

Late error detection at during acceptance.

Client stop trusting the supplier

Schedule and budget overrun.

ASPECT OF RE

Content

Documentation

Agreement

Completeness

Consistency

Necessity

Verifiability

No premature design decision

Correctness and Adequacy

Traceability

Conformity

Understandability

Unambiguity

Agreed

Agreed after changes

Conflicts resolved

PRINCIPLES OF RE VALIDATION

Involvement of the correct stakeholders

Separating the identification and the correction of errors

Validation from different views

Adequate change of documentation type

Construction of development artifacts

Repeated validation

DEFECT DURING RE CHECK

Incorrect requirements

Unrealistic requirements

Superfluous requirements – not needed

DEFECT

System border and context are not represented.

It is not evident, which actor triggers the function.

A data object is not defined but used in a function.

No function is defined that would effect the transition between two states.

Language defects exist.

Symbols with non standard notation are used with no explanation.

Table has empty cells.

Few or none quality requirements.

The measurement methods for quality requirements are insufficient or entirely not defined.

TECHNIQUE RE VALID

STATIC

  1. Reviews
    (informal review, audit/commenting,
    walkthrough,
    inspection)
  2. Matching of different notations

DYNAMIC

  1. Prototypes (behaviour, design, usability)
  2. Simulation(behaviour)

INSPECTION GOAL

Focused validation using a checklist

Clear allocation of roles in the team

Moderation

High error detection rate

Known and accepted rules of the game

Appraisal, no problem resolution

Boosts the team spirit

INSPECTION ROLE

Organizer

Moderator

Inspector

Reader

Scribe

Author

INSPECTION COMPOSITION OF TEAM

Representative of the area of expertise

Domain expert

Representative of the development team

Representative of the Requirements Engineers

ADDITIONAL TECHNIQUE

  1. CHECKLIST

PERSPECTIVE BASED READING

PROTOTYPE

CONFLICT

MGT

Conflict identification

Conflict analysis

Conflict resolution

Documentation of the conflict resolution

ANALYSIS

Data conflict

Interest conflict

Value conflict

Relationship conflict

Structural conflict

SOLUTION

compromise,voting,def of variant, overruling,decision matrix

DOCUMENTATION

Purpose

Avoid repeated treatment of conflicts

Questioning resolutions in case of later issues

Scope

Cause of the conflict

Involved stakeholders

Opinions of the stakeholders

Means of resolving the conflict

Potential alternatives

Decisions and reasons for the decisions