Invalid Actor

Some students may be confused by the term "invalid actor" that we have used in the OOA assignment. Let me explain its purpose for your reference.
An invalid actor is a person or a system outside our system, but this person/system does not deal with our system directly. In such a case, the presence of this person/system may easily  make people confused that they are actors. So, a better way to handle this scearnio is that, after we have reasoned the person/system's eligibilities to be an actor, we document our decision and put it as an invalid actor in the OOA report. In this way, other members/late comers of the project team need not to be confused by the same person/system again.

Example: One may consider that an online shop is an actor of a credit card system simply because a credit card holder may use his/her credit card to purchase items from the online shop and complete a credit card transaction. In many cases, an online shop will send a credit card transaction to VISA or MASTER for payment approval. VISA or MASTER will then interact with our credit card system  to see whether the transaction can be approved. From the above scenario, the online shop does not directly interact with our credit card system. So, by definition, it is not an actor of our system, and further we document it as an invalid actor in the OOA report.

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