A Mobility Management Entity, MME,, configured to select an unmanned aerial vehicle, UAV, application server, UAV-AS, residing in a cellular network to be assigned to a UAV connecting to the cellular network, the MME being operable to: receive (S202, S402, S404) an attach request message originated from the UAV, wherein the attach request message includes information indicating that the UAV requests access information for accessing a UAV-AS, and wherein the information indicating that the UAV requests an IP address of the UAV-AS is included in a protocol configuration options, PCO, field of the attach request message; trigger (S204, S412, S414) selecting, as part of an attach procedure of the UAV to the cellular network, a UAV-AS in the cellular network to be assigned to the UAV, by: - initiating (S410, S412) default bearer establishment by requesting a Packet Data Network Gateway, PDN GW, to create a General Packet Radio Service, GPRS, Tunneling Protocol, GTP, tunnel, wherein one of an Access Point Name, APN, and a User Equipment, UE, Usage Type specified by the UAV are used for default bearer activation and the IP address of the UAV as well as downlink and uplink maximum data rates allowed at the APN level are provided with the response of the PDN GW; respond, to an evolved node B, eNodeB,, with an Initial Context Setup Request message which contains an Attach Accept message, the Attach Accept message including a PCO field indicating the IP address of the selected UAV-AS; provide, using Non-Access Stratum, NAS, Transport messages, the Attach Accept message to the UAV; and establish IP connectivity between the PDN GW and the UAV-AS via the APN so as to enable the UAV to use the IP address of the UAV-AS received as part of the attach procedure to register at the UAV-AS for the upcoming operation of the UAV. receive (S202, S402, S404) an attach request message originated from the UAV, wherein the attach request message includes information indicating that the UAV requests access information for accessing a UAV-AS, and wherein the information indicating that the UAV requests an IP address of the UAV-AS is included in a protocol configuration options, PCO, field of the attach request message; trigger (S204, S412, S414) selecting, as part of an attach procedure of the UAV to the cellular network, a UAV-AS in the cellular network to be assigned to the UAV, by: - initiating (S410, S412) default bearer establishment by requesting a Packet Data Network Gateway, PDN GW, to create a General Packet Radio Service, GPRS, Tunneling Protocol, GTP, tunnel, wherein one of an Access Point Name, APN, and a User Equipment, UE, Usage Type specified by the UAV are used for default bearer activation and the IP address of the UAV as well as downlink and uplink maximum data rates allowed at the APN level are provided with the response of the PDN GW; - initiating (S410, S412) default bearer establishment by requesting a Packet Data Network Gateway, PDN GW, to create a General Packet Radio Service, GPRS, Tunneling Protocol, GTP, tunnel, wherein one of an Access Point Name, APN, and a User Equipment, UE, Usage Type specified by the UAV are used for default bearer activation and the IP address of the UAV as well as downlink and uplink maximum data rates allowed at the APN level are provided with the response of the PDN GW; respond, to an evolved node B, eNodeB,, with an Initial Context Setup Request message which contains an Attach Accept message, the Attach Accept message including a PCO field indicating the IP address of the selected UAV-AS; provide, using Non-Access Stratum, NAS, Transport messages, the Attach Accept message to the UAV; and establish IP connectivity between the PDN GW and the UAV-AS via the APN so as to enable the UAV to use the IP address of the UAV-AS received as part of the attach procedure to register at the UAV-AS for the upcoming operation of the UAV.