Nonfunctional Use Cases

Some nonfunctional requirements can be refined as nonfunctional use cases (also known as infrastructure use cases), such as persistence and encryption, which are described in this section. There are also other kinds of nonfunctional requirements that represent system wide qualities and are described simply as declarative statements during requirements [32, Chapter 7.3]. Although exception handling is a nonfunctional requirement and it would be possible to specify it as a nonfunctional use case, we follow the approach proposed by Rubira et al. [33] and specify the exceptional behavior as use case extensions (Section 5.4.3).

Persist Data [NUC01]
Use Case Name: Persist data
Priority: Essential
Category: Kernel
Actor: system
Inputs and pre-conditions: none
Outputs and post-conditions: data is stored on database
Extension flow of events: none

1. The system stores the data entered by the user on the database

Encrypt Data [NUC02]
Use Case Name: Encrypt data
Description: The system should use a security protocol when sending data over the internet. To have access to the complaint registration features, access must be allowed by the access control sub-system [18].
Priority: Important
Category: Mandatory
Actor: system
Inputs and pre-conditions: none
Outputs and post-conditions: data is stored on database
Extension flow of events:
This extension flow occurs at the extension points Send data over the internet in the Query information, Login, Receive alerts via feeds, Find information on the website, and Specify complaint use cases.

1. The system uses a security protocol to send data over the internet

Provide remote access [NUC03]
Use Case Name: Provide remote access
Priority: Essential
Category: Kernel
Actor: system
Inputs and pre-conditions: none
Outputs and post-conditions: data can be send over the Internet
Extension flow of events: This extension flow occurs at the extension points Send data over the internet in the Query information, Receive alerts via feeds, Find information on the website, and Specify complaint use cases.

1. The system send data over the Internet.