accès architectures astronautics b-isdn broadbandcommunicationsystems computernetworks decisionmaking digitalsubscriberlines earthobservations(fromspace) economicimpact engineering extranets faulttolerance gestion histories history internet intranets isdn managementplanning modems nasaspaceprograms personalcommunicationnetworks radiocommunicationsmobiles remotesensing researchanddevelopment réseauxd'ordinateurs réseauxàgrandedistance(informatique) sonet spaceexploration spaceflight spacemissions spaceprograms spacetransportation systèmesdetélécommunicationsàlargebande technology telecommunicationnetworkmanagement telecommunications telecommunicationsecurity unitedstates virtualprivatenetworks