Requirements and relationship links/connectors

[chris_]

Hi everybody,

I need some information about requirements relationship. The objective is to have a relationship (link) which allow us to "trace" the requirements from High to Low level requirements and/or to show the link into the relationship matrix.  8-)
I have read the EA UML Dictionary concerning the connectors, i.e. how to connect the requirements together, and I need some precision about this.  :-?

1 - For connecting the requirements together, what connector is the more appropriate? Is it more common to use an "aggregation" or "association" into a requirement model?
2 - The connector "Trace" is more for connecting elements which represent the same things but are in different diagrams, is it right?
Example: to trace a requirement in a requirement model to an use case element in an use case diagram.

Thx

chris_

[philchudley]

Hi Chris

For connecting any element to a  requirement then always use a UML::Realization connector. You can create this link, but opening a UML diagram containing the elements (for example a Use Case Diagram), then dargging a single requirement from the project browser and dropping it over a use case on the diagram ... nothing appears to happen ... but trust me a UML::Realization link is made from the Use Case to the requirmement. ALternatively you could use the Realationship Matrix to maintain the UML::Realization links between elements and requirements.

The main reason is that within the RTF documentation generator there as feature for outputting the requirements linked to any element (the same list shown in the Require tab for the element's properties)

As to linking a requirement to a requirement, then it depends upon what you are seeking to model

1) For modelling parent-child relationships I would simply use the project browser heirarchical structure. Dragging a requirement and dropping it over another requirement within the Project Browser will achieve this
2) For modelling links between requirements (for example a design requirement linking to functional requirement), then I would use a "Trace" connector

The above simply represents the way I do modelling, other's may have different opions to offer.

Cheers

Phil

[chris_]

Hi Phil,

thanks for the detailed explanation, it was very helpful to clear the different points
ok, so the "trace" connector can also be used inside the same requirement model. I will try this.  
So, at this point the modeler is free how he actually does the modelling. There is also no default way given by EA concerning what connectors have to be used for a specific model...

Concerning the parent/child relationship, how do we show it the relationship matrix?

Thx


chris_

[philchudley]

Hi Chris

To show a parent-child relationship using the relationship matrix, I suggest that you use a UML::Aggregration link (alternatively you could model the parent-child relationships using a diagram still using UML::Aggregation links from child to parent).

Cheers

Phil

[chris_]

Hi Phil,

Ok, thx for the information, I think I will rather need to use the "trace" connector to link my requirements.

I just have to find out how to modified the type of the existing connectors...  

chris_

[chris_]

I have an additional question concerning the "Trace" connector.  
If the "Trace" link is used to connect 2 requirements, e.g. a low and a high level requirements, the more common is to set the direction to bi-directional, is that correct?

Thx

chris_

[Stefan Bolleininger]

Hello,

i'm a bit confused about the relationship connectors.

i would use the aggregate for a requirement or a trace for a package to fulfill a higher level requirement  

REQ :-aggregate-> higher-requirement <-realize-: Testcase
package :-trace-> higher requirement <-realize-: Testcase

is there a possibility to filter for a requirement traceability that all "higher-requirements" which are hirachially structured got all connectors noted on a rtf?

Element: higher-requirement

Implemented by:   REQ1, REQ2
Tested by: testcase1, testcase2

What types of connector you would suggest me for my usage?

thank you

[Stefan Bolleininger]

Hi again,

does no one has an idea for?

No one did ever needed a traceability for FDA-approval?

How is it possible to report that all customer requirements are designed and tested?
Is there any hint to do that?  

Thank you for answers!