Introduction
Telecommunications networks allow a reduction in distances, time, costs of coordination and links the company by co-operation with its environment. The chain of connectivity becomes vital for the company.
The virtual private networks use the public infrastructure or that of a private operator (as from January 1998 in France) to constitute on a group scale a private network of company enabling him to reduce the constraints of physical space and to maintain the unit of the company by the logical links between the basic functions of its data-processing architecture.
The company can become a virtual company made up of virtual entities established physically in other companies or any other combination of interdependence with companies collaborator, complementary, co-operating, partners, customer, providers, competitors (ex: a great project).
The dedicated networks can be networks of transactions strongly structured with the partners (ex: EDI), of the networks of the co-operative type (ex: sequence of processes), the networks of accèss to shared database (e.g.: places of plane), of knowledge networks with little structured exchanges (ex: academic world), of abstract networks of type electronic mail (e.g.: Internet network).
Standardization of the networks is needed on a worldwide scale in order to guarantee the company's investments. ISO - Uit-t and CCITT are the principal world organizations of standardization as well as CEN in Europe.