The progress of computer sciences and networks associated to the explosion of the web and an exponential growth of electronic edition has seen an evolution of search behaviour. The different communities of students, researchers and all users of documentary information system would like to use a search tool which offers the opportunity to make federated search (or metasearch). Thank to such a tool, it would be possible to search and retrieve at the same time documents or references in our library catalogue and its internal content management system, in other libraries catalogues, or reach and interrogate remote and heterogeneous resources and databases like bibliographic databases or resources available in full-text. This tool could offer the possibility to complete a initial search by providing web resources like subject gateways. This report try to draw up a comparative study of the technologies available in order to set up a federated search tool. It analyses Archimed's software offer as regard in documentary portals with integrated metasearch engine. Lastly, this work gives an overview of the position of the protagonists of electronic edition (commercial or open access, as well as their technologies, projects and partnership in connection with federated search and the question of unique access point in order to reach remote and heterogeneous databases and resources.