Sparx Systems Forum

Enterprise Architect => Uml Process => Topic started by: Magnus on October 23, 2007, 11:57:34 pm

Title: Requirements model
Post by: Magnus on October 23, 2007, 11:57:34 pm
Hi, I've just started looking at the requirements model in EA and just can't seem to grasp what they mean. What I really would appreciate is if someone could give me (or point to) information concerning:
What is the difference between the feature and requirement element?

Thanks in advance.
Title: Re: Requirements model
Post by: thomaskilian on October 24, 2007, 12:48:04 am
It's a philosophic difference. You can well live with just the Requirement element. AFAIR there was also some discussion here on the board and you might try to search for the thread (good luck).
Title: Re: Requirements model
Post by: jeshaw2 on November 06, 2007, 06:05:25 pm
With out searching for earlier threads, nor looking at EA's Requirements model, I'll brashly share my thoughts on the difference.

Requirements are of the stakeholders.  They can be traced back to the stakeholders that state their needs (to be satisfied by the system).

Features are of the system.  They are engineered into the system's design and can be traced to the system elements that make the features available.  Features are often touted by the Marketing folks of pre-packaged software as they search for stakeholders having matching requirements.

In an Engineered to Order system, there is typically a mapping of Requirements to the Features suggested by developers.

In either case, a one-to-one mapping of requirements and features is rare.

Hope this helps.
Jim
Title: Re: Requirements model
Post by: Paolo F Cantoni on November 06, 2007, 08:26:00 pm
Hi Jim,

that's our understanding here...

Following some further discussion, we've concluded that:

You can view  EA Constraints (that which I, alone, must uphold) as Requirements specific to an element and  EA "Internal Requirements" aka Responsibilities as Features (that which I, alone, do) specific to an element.

Paolo
Title: Re: Requirements model
Post by: Magnus on November 07, 2007, 04:11:26 am
Thanks, that really nails it.