A method performed by an entity configured to control a non-access stratum signaling of a mobile entity (100, 400) in a mobile communications network, the mobile communications network comprising at least one slice, the method comprising: - receiving a request message from the mobile entity (100, 400), - determining whether the request message comprises a network slice identifier with which the slice to which the mobile entity intends to connect, can be identified, wherein if the network slice identifier is present in the request message, - it is checked whether the network slice identified by the network slice identifier is allowed for the mobile entity transmitting the request, wherein if no network slice identifier is present in the request message, an attach response message is transmitted to the mobile entity, the attach response message including a network slice identifier for the mobile entity determined based on at least one of subscriber data for the mobile entity and capabilities of the mobile entity, characterized by further comprising - determining whether information about an access point has been received from the mobile entity (100, 400), wherein in the affirmative, - determining a network slice identifier identifying the slice to which the mobile entity (100, 400) intends to connect, for the received access point, - generating a relationship using the determined network slice identifier via which the network slice is related to an access point of the slice, and - transmitting the relationship to the mobile entity (100, 400). - receiving a request message from the mobile entity (100, 400), - determining whether the request message comprises a network slice identifier with which the slice to which the mobile entity intends to connect, can be identified, wherein if the network slice identifier is present in the request message, - it is checked whether the network slice identified by the network slice identifier is allowed for the mobile entity transmitting the request, wherein if no network slice identifier is present in the request message, an attach response message is transmitted to the mobile entity, the attach response message including a network slice identifier for the mobile entity determined based on at least one of subscriber data for the mobile entity and capabilities of the mobile entity, - it is checked whether the network slice identified by the network slice identifier is allowed for the mobile entity transmitting the request, wherein if no network slice identifier is present in the request message, an attach response message is transmitted to the mobile entity, the attach response message including a network slice identifier for the mobile entity determined based on at least one of subscriber data for the mobile entity and capabilities of the mobile entity, - determining whether information about an access point has been received from the mobile entity (100, 400), wherein in the affirmative, - determining a network slice identifier identifying the slice to which the mobile entity (100, 400) intends to connect, for the received access point, - generating a relationship using the determined network slice identifier via which the network slice is related to an access point of the slice, and - transmitting the relationship to the mobile entity (100, 400).