ABSTRACT
The basic unit of an e-commerce function is a data transaction. Es sentially any activity on the Internet such as purchasing a car, transfer ring funds, and negotiating a deal is carried out as a transaction. That is, banking and trading on the Internet will be implemented as a collection of transactions. Each data transaction could contain many tasks. For example, in a banking transaction, the tasks include logging into the system, checking the amount in account A, checking the amount in account B, and transferring X dollars from account A to account B. In the case of trading, the buyer logs into the e-commerce site, chooses the product, clicks on the product, gives his credit card number and then gets a receipt. Both these data transactions are illustrated in Figure 19-1 and 19-2. Note that part of the figure in 19-2 also appeared in Chapter 16 when we introduced the process of e-commerce.
