
The digitization of physical processes through digital applications is now ubiquitous. However, it is not always easy for developers to understand the precise needs of the customer. Therefore, the objective is to make the link between these two actors through a document that summarizes the precise needs of the customer: the functional specifications.
In this article, we will introduce the functional specifications while making the link with the SAP ERP.
Introduction to functional specifications
The functional specifications aim to describe all the functions of a software, a website or an application, in order to determine the functional scope of the project. Indeed, they are based on the expression of the customers' needs and transcribed within the project specifications. Moreover, they are essentially based on the user experience, i.e. on the functioning of the user interface, which differentiates them from technical specifications.
It is also important here to remember that functional specifications are expressed in terms of functionality and not in terms of solutions.
GFS or DFS?
There are two main types of functional specifications: the GFS for General Functional Specifications and the DFS for Detailed Functional Specifications. But in reality, what are the differences between the two?
First of all, the SFG describe a business model, elaborated by the project owner, whereas the SFD are elaborated by the project owner.
GFS
As its name indicates, the GFS represent the general functional specifications. In other words, it is the main functionalities to be provided in the solution. The project owner (customer or client) is the master of the elaboration of this document.
DFS
On the other hand, the SFD represent the detailed functional specifications. Their purpose is to detail precisely the functions described in the SFG. In addition to the main functionalities, the SFDs also include the necessary sub-functions. This time, the project owner (the executor) is the master of the elaboration of this document.
SAP – Functional specifications
Yes, functional specifications also have their place through SAP!
When the business wishes to computerize a complex process in SAP, or simply to be able to use more functionalities (standard and/or specific), it is strongly advised to establish a functional specification. The latter is even indispensable when creating one or more specific programs.
There are several types of SAP functional specifications depending on the customer's needs. There are templates of functional specifications by need. These are based on the acronym WRICEF (or FRICEFW):
Each of these templates includes sections that need to be developed depending on the configuration or development to be done. In addition, SAP offers its own templates directly from its support portal accessible via the following link: https://support.sap.com/.
The content of the SAP functional specifications
Ok, writing a functional specification may seem interesting and useful, we understand the objective. But in reality, what do you really need to write in it?
Generally speaking, in each functional specification, whatever the type of need (workflows, reports, etc.), there are two main parts: the context as well as the design of the solution.
The context
This first part of the functional specification lists information related to the general context of the request. Thus, we find the detailed business process, an explanation that justifies the specific development, the different possible alternatives, the dependencies with other programs, the relevant links....
The design of the solution
This second part of the functional specification lists information related to the conception and design of the solution. Moreover, this part can vary slightly depending on the type of need. Thus, we find the design of the user interface, the necessary authorizations, the flow diagram, the management of validation steps or errors...
To conclude
Depending on your working methods (agile method, V-cycle...), the design modes of the functional specifications will change. For example, in V-cycle, the functional specifications are detailed at the beginning of the project while in agile method, they are built as the project progresses.
In any case, a correctly written functional specification will undoubtedly allow the solution to be put into production quickly and functionally. It is therefore very advisable to attach particular importance to it.
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Pierre Balbinot
SAP functional consultant, EAM (Enterprise Asset Management) and PP (Production Planning) expert.
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