Requirement Types

Each requirement or referenced requirement has a requirement type that specifies its role. The requirement type is specified by the Type property of the slreq.Requirement object or slreq.Reference object.

Built-in Requirement Types

You can use these built-in requirement types when authoring or importing requirements:

Functional: Use functional requirements to capture required functional behavior for the design. Requirements Toolbox™ calculates the implementation and verification status for functional requirements based on the requirement links.
Container: Use container requirements to organize your requirements in groups and create a hierarchy. Requirements Toolbox does not include container requirements when calculating the implementation and verification status of the requirement set. However, any functional requirements under a container requirement contribute to the calculation of the statuses.
Informational: Use informational requirements to capture non-functional behavior or other supplemental information. Requirements Toolbox does not include informational requirements or any requirements under them when calculating the implementation and verification status of the requirement set.

For more information about implementation and verification status, see Track Requirement Links by Using Implementation Status and Review Requirements Verification Status.

Custom Requirement Types

You can create custom requirements by extending one of the built-in types to define a requirement type that aligns with your project. For example, you can create custom types for system or stakeholder requirements. You can use stereotypes to define custom requirement types that have custom properties, or define custom requirement types by using an sl_customization file. For more information, see Define Custom Requirement and Link Types and Properties.

Custom requirement types must use one of the built-in types as the base behavior. The custom requirement type inherits some functionality from the built-in type, including how the requirement type contributes to the implementation and verification statuses. For more information, see the Choose a Built-in Type as a Base Behavior section of Define Custom Requirement and Link Types and Properties.

Set the Requirement Type

When you create or import requirements in Requirements Toolbox, you can specify the requirement type in the Requirements Editor by clicking Show Requirements and, in the right pane, under Properties, selecting the type from the Type list. You can then choose from the built-in requirement types or your custom requirement types.