What is important in IT, it is the number of achievable separate applications thatit is necessary to generate for the whole of the software. This, because it is necessary to complete a certain work to adapt a software so that it turns on a specific material or a different environment, i.e. a target machine of different type: OS (operating system of the machine) and/or screens and/or flows of communication and/or computing power of the machine.
One can characterize these types of achievable separate applications by “types of target machines”.
It should be noted that if the differences between target machines are too important, as well as the efforts to arrive at the result, the adaptation to a kind of environment targets can be regarded as a sub project.
The“Types of target machines” can be:
- Functional:
- a waiter application or a customer application;
- a real time distributed application: a module turns on petrol pump, the other on the exchange of the station with petrol which is interfaced with the bank for the payment;
- pieces of an application of distributed calculation being carried out on parallel machines which treat each one part of the total treatment with a machine which supervises;
- an embarked software on a mobile object, e.g: a plane comprising several treatment units which dialogue between them with a central calculator.
- Physical: when one wishes to test the application on different material architectures:
- an application which turns on PC, Tablet or Smartphone;
- a website with a posting and menus planned specifically for shelf and Smartphone.
- Environmental: when one wishes to test the application on different OS: an application on Linux, Windows, MAC, Unix.
NOTE: Compilers and IDE (Integrated Development Environment) make certainly it possible to rather easily ensure in many cases the passage under different OS like Unix/Linux/Windows/Mac, but that nevertheless requires a work of production of the achievable correspondents and sometimes a complete recasting as for Android or an OS real time.
On the low floors of the tree structure of Zones are the types of target machines. These Environment or Zones can be physical, which gives the name of this tree structure: GBS, for Geographical Breakdown Structure. The concept of geography returns here to that of material architectures.
In addition, overallconcept the “of functionalities” prevails in the structuring of an IT project. This concept is thus at the top of tree structure of the 3D WBS. Activities are deployed on modules (a family of functions) which are assigned to functional Zones. Each functional Zone understands a set of functionalities.
It should be noted that in the two other tree structures of the 3D WBS, i.e. the Products (PBS, Product Breakdown Structure) and the Activities (ABS, Activity Breakdown Structure), one finds on the high floors of these tree structures abstract concepts (functional systems and macro-Activities) and on the low floors of these tree structures concrete concepts (components/equipment/works, precise Activities).
The following figure illustrates the tree structure of the Zones for an IT project.
The concept of version of the software is to be specified. Basically, a version is an evolution of the functionalities of a module (Product). According to 3D WBS, a version can thus be seen as an instantiated Product - since two different versions from the same module are carried out starting from the same Activities.
More generally, as on all types of projects, even if they are industrial, of infrastructure type, Product development and even IT, Zones are of Physico-functional nature.
Written with Sylvain LE MUET DELAYS