I am trying to model an Information System.
At the OA stage, I have 2 Actors that are going to be users of the IS but which are part of 2 different organizations.
I have modeled these 2 organizations as 2 Entities. And then I have my 2 Actors, each one being contained in its “organization” Entity.
Now, if I want to express that these 2 Actors can be seen as “Users of the IS”, how can I model that?
I can create a “User” Entity, but I can’t link my 2 Actors to this new Entity without losing the link to their “organization” Entity.
I can create a “User” Actor, but I can’t link my 2 Actors to this new Actor.
You can create the “User of the IS” role , allocated Operational activities to this role, and define your 2 Actors as “User of the IS”.
Indeed this makes sense. Nevertheless, in my OAB, I end up representing my 2 Actors, but they both have the same activities, so I have the impression that it makes more sense to have a “User” entity so that I can work directly with this entity in the OAB instead of duplicating the activities and interactions for both actors. WDYT ? Does using roles helps in any way regarding to this point ?
It depends what do you want to model. Generally, in OA, it is important to distinguish the different actors/entities because the goal is to model what the users of the system need to accomplish. If you share the OA with a customer, it can be disturbing for him, if he can’t find the different actors.
The role is very useful in the case where 2 actors have similar operational activities but also different operational activities.For example, if you have one entity Computer, 2 operational Actors Policeman and Computer Administrator, it can be useful to define a role Computer User with some allocated activities as Start computer, … etc
The Policeman can have extra operational activities as Research a person and the Computer Administrator can have other extra activities as define right access(see picture: OA without OP.
Like that, we can see the common and not common activities allocated to the Policeman and the Computer Administrator. Moreover if we add a new activity to the User computer role, of course it means this activity is allocated to both operational actors.
But there’s an issue with the role: if you build an operational process Research a person, involving the operational activity Start computer if you display this OP in one OAB displaying both operational actors and all the operational activities, Capella displays the Start computer of the Policeman and the Start computer of the Computer Administrator as a part of the operational process because it is the same operational activity (see picture: OA with OP).
I’m not sure to answer your question but rather make you ask more
Thank you Sebastien for all your explanations.
Actually, my point was the following: in my example, let’s say that I have not 2 actors, but 20 actors. There are all from different companies (20 entities then), and all these actors have about 6 identical activities, so I end up having an OAB which becomes quite difficult to read as it has a lot of duplicated information.
This is really a theoretical question here, I solved my problem by stopping to link my actors to their company entities because it made more sense from a modeling viewpoint to emphasize that they were all linked to the entity “SI User” and named my actors “Company A User”, “Company B User”…
Still, the customer could argue that the link between the company entity and the corresponding actor is missing, as for other reasons I have to have the company entities…
Jean-Luc Voirin notified me there’s a risk with my previous post to confuse: this diagram could be understood as the system of interest is the Computer. And we must not model the system of interest in operational analysis because the goal of this layer is to model the needs of the users, not to define the responsability/borders of the system of interest. He suggested me this diagram in order to illustrate the Role concept in Capella: