Patent ID: 8467769

Claim:
A method for identifying a host-type radiocommunications network of a user terminal from at least two networks forming a radiocommunications infrastructure which comprises: a base station shared by the at least two networks, said base station being configured to: ensure radio transmission and reception with said user terminal located in a cell attached to said base station, and route data between said user terminal and each of said at least two networks; a network core for each of said networks, each network core comprising: an authentication and checking device configured to authenticate and check user terminals, and a database containing information relating to the access rights of user terminals to one of said networks, each user terminal having a unique user identification code comprising: a first network identifier code, and a second code identifying a user of the host network, wherein when said user terminal is located in a cell and said user terminal transmits for the first time a request for attachment to one of said networks via its unique identification code, said method comprises: checking the access rights of said user terminal to said radiocommunications infrastructure based on said first network identifier code, and pre-decoding said second code to identify the host network of said user terminal and routing the attachment request of said user terminal to the authentication and checking device of the identified host network, said authentication and checking device configured to authenticate said user terminal.