Contenu du sommaire

Firstly, telecommunications and telematics technologies are now being applied to all aspects of the functioning of utility networks. Secondly, the control capabilities of telematics are helping to support a convergence and cross-investment between previously-separate utility systems. These trends have important implications for the management and development of cities which the paper explores in its final section.

The paper discusses the nature and the composition of urban networks. It proposes an operative definition of some basic components: networks of organization, networks of cities, local networks, nodes, urban milieu, urban systems. Composing these elements at two levels, global and local, it is possible to classify the actual different cases of urban development and structure in four ideal types. These typologies are based on the degree of local integration and external functional openness of the urban systems, considered as self-organized local nodes of global networks.

German unification changed the environment and the performance requirements of both German telephone systems. Using the projections of the future network structures as a guideline, this paper analyzes the decision- making process (November 1989 - December 1990) on their technical reconfiguration. First, the system's corporate actors developed a program that followed their interests, but neglected the acute needs. Adaptation to the performance requirements of the environment had to be enforced by the threat of major interventions into the telephone system. The structure of the technical basis of the new German telephone system can be understood as the results of the interaction among a set of corporate actors, since their interests and their acting shaped the technical configuration and the strategy to introduce this configuration.

In this paper, it is shown how the logic that shapes the city-system is more complicated than the simple "territorial" and hierarchical logic of the traditional central-place model. The control of the market of outputs, inputs and innovative assets is performed by the firm, not only in terms of management of a gravity area, but also and increasingly in terms of network relationships. The new behavioural logic of the firm parallels and partly determines the new organisational logic of the city system, where phenomena of specialisation and networking also appear. Probability of interaction among cities may go far beyond what is expected on the basis of their size and distance. High density of information flows on a proximity basis, as for those taking place within specialised industrial "districts"; cooperation and spatial division of labour among specialised centres; and synergy among similarly specialised centres linked through high- performance information networks, are all elements calling for selected non-hierarchical linkages among centres, which we call "city networks". In the empirical realm of the Lombardy region, network relations among centres were discovered, mainly showing up in two specific spatial contexts: within the metropolitan area of Milan, shaping its emerging policentric structure; and within sub-regional industrial districts. In the first case, the empirical evidence suggests the existence of "synergy networks," occurring among similar centres performing headquarter and advanced production-services functions; in the second case, mainly "complementarity networks" and "milieu" type of interactions are revealed.