To that data processing

The data-processing audit (also called audit of the Information systems) is the evaluation of the risks of the computer operations, with an aim of bringing a reduction in those and of improving the control of the information systems.

The listener bases himself on the reference frames according to:

  • COBIT (describing the complete operation of a data processing department)
  • Standard ISO

cf isaca or afai

---- the following part does not correspond to the definition of the data-processing audit retained by the profession: ----

There exist two types of to that data processing :

  • the audit of the need;
  • the audit of discovered knowledge.

Audit of the Need

The audit of the need comprises two parts:
  • analysis of what exists;
  • determination of the target.

The analysis of existing consists of a work of ground at the end which one formalizes the circulation of the documents " types" from one actor to another and the treatment which each actor applies to these documents, using Logigramme S (treatments on the documents) and of representation of relational Graphe S (circulation of the documents).

The determination of the target consists in locating:

  • the passages " paper - numérique" and " numerical - papier" ;
  • redundancies in the graph (" forms in several exemplaires") ;
  • bottlenecks (dispersion of the infrastructures, check-points and validation necessary?) ;
  • cutting in zones, subgraphs: the " fields; métier". Thus each zone can be equipped with a specific tool, rather than only one total system " machine with gaz".

Thus the result of the audit, generally worked out and collectively approved, can give place not to a project, but several projects scheduled in a roadmap.

Audit of Discovered Knowledge

The audit of discovered knowledge consists in developing the existing data and knowledge in the company. The mathematical modeling of the databases always obliges with " perdre" part of information, it acts to redécouvrir it in " brassant" data.

One audit of discovered knowledge generally leads to the assembly of a decisional system, but also to be the prelude to a management system of knowledge.

The audit of discovered knowledge is practiced in the following way:

  • No objectives: one does not know what one will discover;
  • a field: one knows about which trades one works, therefore about which databases;
  • an integrated team: work in situ, three actors of which an expert " métier" , an expert " administration informatique" and a digger of data (see Dated mining)
  • work is done by short loop of prototyping
  • to facilitate the mixing of the data, one modifies their format and their relative tendency. It is the " preprocessing" who takes the most time
  • Using algorithms with training on the one hand, and of visualizations of data on the other hand, the digger highlights empirical bonds between the data
  • the correlations and bonds selected must answer three criteria: unknown to the user, explainable a posteriori and useful. The theoretical demonstration of the phenomenon is completely superfluous.
  • detected knowledge is formalized (trees, graphs, tables, rules, etc) then prototypées logiciellement
  • the validity of prototypées knowledge is checked thanks to a statistical test (khi two, kappa, etc) on a data file known as " test set" , different from the play having been used for the analysis (" training set")
  • the test set can be either external with training set, or recomputed from him (rééchantillonnage)
  • If the test passed, the model is put in production
  • One starts again the cycle.

Concretely, the stacking of the models, themselves sometimes complex (trees and Récursivité) can lead to truths problems of data-processing architecture:

  • Parallelization of calculations
  • Volumetry of the data
  • Load of the network, partly due to the mechanisms of replication
On another side, the computation result resulting from a stacking of models can lead to results particularly relevant and surprising.

Random links:Nuclear plant | Sabinea | Novi Beograd | XMLTV | Howard Blake | James_Duggan