Software Requirements Engineering Lecture 7: Negotiation PDF

2 TEACHING GOALS  Learn the meaning of the term “conflict”  To know the significance of conflicts with regard of requirements  To know the types of requirements conflicts  To know the various conflict resolution techniq...

2 TEACHING GOALS  Learn the meaning of the term “conflict”  To know the significance of conflicts with regard of requirements  To know the types of requirements conflicts  To know the various conflict resolution techniques  To know the documentation of conflict resolution 3 R E F RA M E W O R K 4 DEFINITION OF REQUIREMENTS N E G O T I AT I O N The goal of the negotiation activity is to 1. Identify conflicts D 2. 3. Analyse the cause of each conflict Resolve the conflicts using appropriate strategies 4. Document the conflict resolution and the rationale 5 CONFLICT A conflict in requirements engineering exists, if D the needs and wishes of different stakeholders (or groups of stakeholders) regarding the system (partially) contradict each other, or if needs and wishes cannot be considered. 6 REQUIREMENTS CONFLICT - EXAMPLES  A group of stakeholders demands the use of radar sensors for distance measurement. Another group of stakeholders asks, instead, for ultrasound sensors.  A stakeholder demands to display safety-relevant information for the driver on a head-up display. Other stakeholders argue this would distract the driver and hence reject this requirement. 7 CONFLICT MANAGEMENT The goal of the negotiation activity is to : Identify Analyze the Resolve Document the conflict (cause) conflicts the conflict conflicts resolution of each conflict by means of and the rationale appropriate strategies 8 IDENTIFY CONFLICT – Conflicts may surface during all requirements engineering activities. – Conflicts are often not easy to detect:  Pay attention during all RE activities to detect and document (possibly latent) conflicts.  Similar conflicts should be consolidated (e.g. different conflicts about the same goal or requirement). – Actively search for conflicts! 9 A N A LY Z E CONFLICT – A conflict can have several causes – For each identified conflict, – Determine all reasons behind the conflict and – Identify the conflict types for all reasons – There are 5 conflict types 10 5 CONFLICT TYPES Data conflict – Is caused by a lack of information, by misinformation, or by different interpretations of an issue. Interest conflict – Is caused by subjectively or objectively different interests or goals of stakeholders. Value conflict – Is caused by different criteria which stakeholders apply when evaluating an issue (e.g. cultural differences) Relationship conflict – Is caused by negative interpersonal behavior among stakeholders (e.g. disrespect, insulting) Structural conflict – Is caused by an unequal balance of power between stakeholders 10 11 R E S O LV E CONFLICT – Has impact on future co-operation (motivation) of the stakeholders – Important : Involvement of all relevant stakeholders – Conflict resolution techniques : Agreement Negotiate the solution Compromise Found through combinations of alternatives solutions Voting Each stakeholder gets to vote Definition of variants Solve the conflict through system variants and/or parameters Overruling Decision is made hierarchically Consider-all-facts All influencing factors are considered Plus-minus-interesting All positive and negative effects are evaluated Decision matrix Often named as benefit value analysis 12 R E S O LV E C O N F L I C T - S T RAT E G I E S Resolve conflicts by using the following strategies: Negotiation Creative Solution Decisio n Initial situation: – The car safety system shall be equipped with radar technology in order to E monitor the traffic ahead of a car. Example of Conflict – There is a conflict among two groups of stakeholders regarding the distance up to which the radar sensor shall monitor the traffic in front of the car.  Resolve conflict using Negotiation : – The stakeholders resolve the conflict using the negotiation strategy by agreeing on a detection range of 750m.  Resolve conflict using Creative Solution : – Stakeholder B argues for 500 meter distance because a 1000 meter distance measurement by radar sensor would cause higher costs. If a 1000 meter distance measurement would not lead to an increase in costs, he would prefer a 1000 meter distance measure. – By equipping the car with a laser sensor instead of a radar sensor the detection range is increased to 1000 meter without causing additional costs.  Resolve conflict using Decision : – As the conflict exists between two groups of developers, the client is 14 DOCUMENT THE CONFLICT Conflict Resolution Strategies and Type of Conflict Conflict type Negotiation Creative solution Decision Data suitable not suitable not suitable Interest suitable conditionally suitable suitable Value conditionally suitable conditionally suitable suitable 15 DOCUMENT THE CONFLICT  Purpose – Avoiding 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 16 W I N -W I N APPROACH  Goal – Make all stakeholders become winners during conflict resolution.  Three principle situations – Win-Lose Some stakeholders achieve their goals at the expense of other stakeholders. – Lose-Lose No conflicting party achieves its goals – Win-Win All conflicting parties achieve their goals completely or partially 17 SUMMAR Y Conflict management comprises identifying, analysing and resolving conflicts as well as documenting the conflict resolution. Goals and scenarios support requirements negotiation. Conflicts may surface during all RE activities – but are not always easy to detect. Conflicts can be classified by five conflict types. Negotiation, creative solution and decision are three basic resolution strategies for data, interest and value conflicts. The win-win approach is a negotiation technique. 18 REFERE NCE  Klaus Pohl, Requirements Engineering Fundamentals, Principles and Techniques 1st edition, Springer, 2010.