Modeling a simple Copy Card with SecureMDD

Modeling an application is an iterative process. Here we present a linear walk-through.

The CopyCard is a smart card that is actually a simple E-Wallet, i.e. it contains money, and it is possible to load money onto the card and to pay with the card.

We begin with UML sequence diagrams for getBalance, load, and pay:

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  Everybody can check the balance on a copycard.
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  To load mony onto a card the card must be sure that the terminal is genuine. Therefore an authentication step is required before the actual load message can be sent.
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  For payment the terminal must be sure that the card is genuine. The necessary information is contained in the response from the card.

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