1. A mobile station comprising an end device (ME) and comprising a removable or fixedly implemented security element ((U)SIM) operable in the end device (ME), a bond being established between the end device (ME) and the security element ((U)SIM), such that the end device (ME) and the security element ((U)SIM) are only operable together in accordance with the bond, a secret key (PrK; KST) being stored in the security element ((U)SIM) and a verification key (PuK; KSA) corresponding to the secret key being stored in the end device (ME), such that the bond between the end device (ME) and the security element ((U)SIM) can be verified by means of the secret key (PrK; KST) and the verification key (PuK; KSA; wherein the end device (ME) comprises a secured runtime environment (TEE) and the verification key (PuK; KST) is stored in the secured runtime environment (TEE).