A subscriber identity element authenticates a communication device to a communication network. The subscriber identity element is assigned a subscriber identity identifier. The communication network comprises a subnetwork having a discovery server. The subscriber identity element comprises: a memory in which an initialization profile of the subscriber identity element is stored, wherein the initialization profile indicates a subnetwork identifier the subnetwork; and a communication interface, configured to establish a communication link to the discovery server using the subnetwork identifier and to transmit the subscriber identity identifier to the discovery server via the communication link.