Software Engineering

11.2.1 
Identify functional scenarios
The software products support many operational scenarios that should have been 
identified by the software requirements specification. The functional scenarios rep-
resent abstract sequences of data processing actions that are necessary to enable the 
software product to facilitate the business or operational process. Each operational 
scenario should be evaluated to identify the assortment of functional scenarios that 
must be designed for. For example, an automated teller machine (ATM) supports 
several distinct banking (business) transactions. Each banking transaction must be 
evaluated to identify the various situations that would trigger a separate functional 
scenario. These situations include: (1) the bank account is inactive due to customer 
closure, (2) the bank account is suspended due to inappropriate account activity, (3) 
the bank account contains insufficient funds to support the requested transaction, 
and (4) the bank account has sufficient funds to support the requested transaction. 
Each of these situations represents a functional scenario the software product must 
be designed to support.