How to guide in 5 steps

what is a map?

The term “map” refers to a diagram illustrating a set of information. The information shown is carefully chosen to provide an effective response to the question(s) raised.

Maps are typically organised into different dimensions. For example, geographical maps incorporate road infrastructure and towns in line with users’ needs.

A varying amount of information can be displayed depending on the requirements. For example, we might choose to show altitude, service stations or toll booths on the map.

Map of the information system

In a digital context, a map provides a visual overview of an organisation’s information system (IS) as well as its external connections. This overview can be more or less detailed and include, for example, the hardware assets, software, connection networks as well as the information, activities and processes which rely on these assets.

In practice, mapping must make it possible to:

• draw up the inventory of the assets of the IS, i.e. the list of its
  components and their detailed description;
• present the information system in the form of views, i.e. partial
  snapshots of the information system, its links and its operation.
  These aim to shed light and clarity on the different aspects of the
  information system.

Elements making up a map

As a general rule, the map comprises 3 visions going progressively from business to technical aspects, themselves broken down into views:

• Business vision
  • the ecosystem view presents the various entities or systems with which the IS interacts to fulfil its function;
  • the business view of the information system shows the IS from the perspective of its main information and processes (named business assets in the risk assessment method EBIOS Risk Manager).
• Application vision
  • the application view describes the software components of the information system, the services they provide and the data flows between them;
  • the administration view lists the privilege levels and scopes of users and administrators.
• Infrastructure vision
  • the logical infrastructure view illustrates the logical network partitioning, particularly by defining the IP address ranges, VLANs and filtering and routing functions;
  • the physical infrastructure view describes the physical devices making up or used by the information system.

The views are made up of different objects, examples of which are given in Appendix 1. In each view, a pivot object shows how this view links up with the adjacent views, making it possible to identify dependencies between the objects of the information system.