The invention is a method for authorizing a device to establish a communication session with an access point of a WLAN. A secure token comprises a data related to a telecom network subscription and is connected to the device. The device comprises credentials required for establishing the communication session with the access point. The method comprises the following steps: asking the secure token to initiate an authentication by using the data, running an authentication process initiated by the secure token by using the data and a communication channel provided by the telecom network, in case of successful authentication, sending an authentication pattern from the secure token to the device, authorizing use of the credentials thanks to the authentication pattern in the device and establishing the communication session between the device and the access point by using said credentials.