Abstract: A method for opening a session of a first machine using a session checking service for the first machine and a second machine, including a security service, includes receiving a request to open a session on the first machine, the request including a user identification information item; verifying that the identification information item is associated with an identification data item of the second machine in a repository; checking that the user has the right to open the session on the first machine; if the verification and check are positive, sending a session status modification request of the second machine to the security service of the second machine; if the session status of the second machine is modified, sending a request to authorize opening of the session to the first machine; and storing the identification information item associated with an identifying data item of the first machine in the repository.