A Cybersecurity Requirement Diagram displays cybersecurity goals, cybersecurity requirements, and their relations. The main purpose of this diagram is to create requirements that cover the goals defined in TARA. 

Deriving Cybersecurity Requirements

Cybersecurity Requirements are derived from Cybersecurity Goals defined in a TARA table. You can use the Cybersecurity  Requirement Diagram to derive four types of Cybersecurity Requirements: Functional, Technical, Software, and Hardware.

To derive a Cybersecurity Requirement

1. From the Index page, open the Functional Cybersecurity Concept.
2. Find the Cybersecurity Goal you want to derive the Cybersecurity Requirement from and drag it to the diagram.
3. Create the Cybersecurity Requirement you want to derive by clicking it in the diagram palette and clicking an empty space on the diagram pane.
4. Name the created Cybersecurity Requirement and write the required text.
5. Create a derived relationship from the Cybersecurity Requirement to the Safety Goal as displayed below.
   
   

Creating a Cybersecurity Goal

To create a Cybersecurity Goal

1. In the Containment tree, right-click Functional Cybersecurity Concept and select Create Element.
   
   
   
   
2. Do one of the following:
   • In the dialog, expand ISO 21434 and select Cybersecurity Goal.
     
     
     
     
   • In the search tab, type the keyword goals and then select Cybersecurity Goal.
     
     
     
     
3. Name the created Cybersecurity Goal in the Containment tree. The cybersecurity goal has the prefix CG, which denotes that the created element is cybersecurity goals; the number 1 indicates that it is the first cybersecurity goal created.
   
   

Creating a Cybersecurity Requirement

To create a Cybersecurity Requirement

1. In the Containment tree, right-click Functional Cybersecurity Concept and select Create Element.
   
   
   
   
2. Do one of the following:

   • In the dialog, expand ISO 21434. From the drop-down list, choose one of the following:

     • Functional Cybersecurity Requirement
     • Hardware Cybersecurity Requirement 
     • Software Cybersecurity Requirement
     • Technical Cybersecurity Requirement
       
       
       
       
   • In the search tab, type the keyword goals and then select the required Cybersecurity Requirement.
     
     
     
     

3. Name the created Cybersecurity Requirement in the Containment tree.
   
   

Functional Cybersecurity Concept Table

The Functional Cybersecurity Concept Table provides an overview of goals & requirements to be implemented to secure assets.