Once you have initially created the service interface, you define its functionality by creating a series of operations using the Interface Mapper. Generally, an operation represents an interaction with a single program entry point. In the Interface Mapper, you work with one operation at a time.
A single service interface typically contains multiple operations. For example, if you know that a single entry point leads to an EVALUATE statement choosing between different functions, you could define a separate operation for each one of these functions. Often in such a program, one parameter is a parameter tested by the EVALUATE statement to see which function is specified.
All operations are packaged together into one service, but each operation is independently executable (i.e., only one operation is invoked per service execution).