Task: Model a Scenario |
Define the internal behavior that allows the business to accomplish its goals. The result is a business use-case realization that is used to understand or re-engineer the business.
Disciplines: Business Modeling
Purpose
To define business operations that fulfill the business described in the business use cases. To define a business model for the business. To provide the means for defining services that fulfill the goals of the business.
Relationships
Roles | Primary Performer: Business Analyst | Additional Performers: Stakeholder
Inputs | Mandatory: Business Use Case Business Use-case Model [Business Design] Business Model Functional Area Model | Optional: Business Model
Outputs | Business Model
Main Description
Create representations (operations and ordering) of the behavior the business needs to perform in order to fulfill specific scenarios described in the business use cases. This is represented by business elements such as business components or areas, services, workers, entities, etc. These white-box or internal descriptions of the business are organized as use-case realizations; each use case has a corresponding realization where all the white-box descriptions of the scenarios are maintained. This makes it easier to organize and understand how the business must operate in order to fulfill the behavior described in the business use cases. The result of this task is a set of business descriptions that can be used for business re-engineering and the identification of system services for automation. Diagrams and elements from the Rational UML Profile for Business Modeling are used to describe the internal working of the business. See the Whitepaper: Effective Business Modeling with UML: Describing Business Use Cases and Realizations for more detail on how to create business use case realizations.
Steps
Identify scenarios to define
Find scenarios in the business use cases that will be refined into descriptions of how the business accomplishes those scenarios. Generally, high-priority or critical scenarios are the first that are selected for refinement into business use-case realizations. It can also be useful to create UML activity diagrams of the candidate scenarios to determine their criticality and provide input to later steps in the task. Create a sequence diagram for each selected scenario, and place it in a business use-case realization that realizes the business use case. Create the realization if one doesn't exist, and add a realization relationship from the realization to the use case on a Business Use-case Realization diagram. See Describe the Business for details on creating and adding sequence diagrams to the business use-case realization.
Identify business elements
Use the business use-case scenario to identify an initial set of business elements that will be used in the business use-case realization. Often, a collection of elements found earlier can be used before creating new ones. Examine the [Business Architecture] for business elements that are implicitly or explicitly described, and that can contribute to fulfilling the business use-case scenarios you're working on. See Finding Business Workers and Entities for information on how to find workers and entities. Also, see these examples of workers and entities and their interactions.
Understand how elements interact
Show all actions required to produce the scenario by describing them in a sequence diagram created in the business use-case realization. Add or use existing operations to business elements that show the behavior they need to perform in order to realize the scenario. Use existing operations whenever possible as this will make future normalization tasks easier. Identify new business elements as appropriate. Be clear how you reach each step of the sequence diagram. There must be no ambiguities in understanding how to get from one step to the next. See Guideline: Describe a Business Use-Case Scenario in a Business Use-Case Realization for guidance on illustrating the behavior that realizes a scenario.
Identify relationships in the scenario
This step is optional, though it can be useful to identify the structural relationships between business elements that participate in the sequence diagram. Create a class diagram showing the required relationships between the workers and entities to support their interactions in the sequence diagram. See Guideline: Identify the Structure of a Business Use-Case Realization.
Refine relationships based on architectural constraints
Use the [Business Architecture] to identify relationships between business elements that need to be refined. It's possible the business architecture defines constraints or patterns that illustrate how some elements need to interact. This allows the use-case realization to take into account different organizations, regulatory requirements, the physical distribution of the organization, and other issues that are not obvious when examining the use case scenario by itself.
Achieve concurrance
Gain agreement between stakeholders and business analysts that the way the business is described will achieve the business's goals. This agreement is based on the experience and thoughtfulness of the participating roles because to-be processes are by definition untested.
More Information
Concepts | Business Entity Business Use-Case Realization
Whitepapers | Effective Business Modeling with UML: Describing Business Use Cases and Realizations
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