Patent ID: 9450949
Filing Date: 2016-09-20
CPC Classification: G06F,H04L

Claim Text:
1. A method for access control to a computer by means of a mobile end device, wherein the mobile end device and the computer each comprise a contactless interface, wherein, using the contactless interfaces, an authentication to the computer is carried out with the mobile end device and upon a successful authentication the access to the computer is granted or maintained, wherein: for preparing the authentication, a certificate is loaded into the mobile end device from a portable data carrier separate from the mobile end device; for authentication, authentication data comprising the certificate or obtained from the certificate are made available to the computer from the mobile end device via the contactless interfaces, the authentication data being sent in response to an authentication invitation sent at an interval by the computer; the certificate has a limited-time validity which is limited in time for a predetermined period of validity; upon an attempt of authentication which is carried out outside the period of validity of the certificate, it is requested that a certificate is loaded into the mobile end device anew loaded from the portable data carrier into the mobile end device; and upon receiving an authentication invitation, the mobile end device is shifted from a power-saving first mode with restricted functionality of the mobile end device to a power-saving second mode with restricted functionality of the mobile end device in which at least the carrying out of the authentication is possible, the power-saving first mode having more restricted functionality than the power-saving second mode.