03.643GPPGeneral Packet Radio Service (GPRS)Overall description of the GPRS radio interfaceStage 2TS
The purpose of the Physical Link layer is to convey information across the GSM radio interface, including RLC/MAC information. The Physical Link layer supports multiple MSs sharing a single physical channel.
The Physical Link layer provides communication between MSs and the Network.
The Physical Link layer control functions provide the services necessary to maintain communications capability over the physical radio channel between the Network and MSs. Radio subsystem link control procedures are currently specified in GSM 05.08 [15. Network controlled handovers are not used in the GPRS service. MS performed cell-reselection is used, see subclause 6.5.6.