The invention concerns a method and a system enabling users (11) of an Internet type computer network provided with multimedia terminals (16) comprising a microphone (17) and connected to an Internet type computer network (15), remotely located from a service supplier (12), to accede rapidly and safely, to services (30) offered by this service supplier (12). The method comprises the following steps: the service supplier (12) provides each of the users (11) of an Internet type computer network (15) who have subscribed to his services (30), a card, formatted like a credit card; said card (10), formatted like a credit card, emits brief identifying sound signals (20), of the DTMF type, at least partly encrypted, varying with each operation, when it is actuated (14) by the user (11); said identifying sound signals are received by the microphone (17) of the multimedia terminal (16) and transmitted via the Internet type computer network (15) to the computer service (18) of the service supplier; the transmitted signals and the identification data of the subscriber and the card in the possession (23) of the computer service (18) are electronically processed (24) and compared (25) by the computer service. In the event of coincidence, the subscriber is immediately put through to the services (30) of the service supplier (12).