A method in a in a Base Station Subsystem (BSS) for receiving a service identifier from a packet core network is provided. The BSS receives a service identifier in a BSS General Packet Radio Service (GPRS) Protocol (BSSGP) Downlink unitdata Protocol Data Unit (DL-UNITDATA PDU) that includes a Logical Link Control (LLC) PDU comprising a data packet or a portion of a data packet from a Serving General packet radio service Support Node (SGSN) which service identifier is identifying a type of service for the data packet, wherein receiving the service identifier in the DL-UNTIDATA PDU comprises receiving, within a header of the DL-UNITDATA PDU, a value corresponding to the service identifier. The BSS performs an action based on the service identifier.