A device for service layer registration, the device comprising: a processor; and a memory (44; 46) coupled with the processor, the memory (44; 46) comprising executable instructions that when executed by the processor cause the processor to effectuate operations comprising: sending, by a first application entity,AE, (20; 20') of the device, a first message comprising a registration request for a first service of a oneM2M service layer to a first oneM2M common service entity, CSE, providing a first registrar entity; receiving a second message that is responsive to the first message, the second message comprising a first list of one or more identifiers of one or more services granted by the first registrar entity for the first application entity (20; 20'), wherein the second message further comprises a valid time, wherein the valid time indicates an effective time period for which the first service is provided to the device; sending, by the first application entity, AE, (20; 20'), a third message comprising a registration request for a second service of the oneM2M service layer to a second oneM2M common service entity,CSE, providing a second registrar entity; and receiving a fourth message that is responsive to the third message, the fourth message comprising a second list of one or more identifiers of one or more services granted by the second registrar entity for the first application entity (20; 20'); wherein the first application entity,AE, (20; 20') is simultaneously registered with the first registrar entity and the second registrar entity. a processor; and a memory (44; 46) coupled with the processor, the memory (44; 46) comprising executable instructions that when executed by the processor cause the processor to effectuate operations comprising: sending, by a first application entity,AE, (20; 20') of the device, a first message comprising a registration request for a first service of a oneM2M service layer to a first oneM2M common service entity, CSE, providing a first registrar entity; receiving a second message that is responsive to the first message, the second message comprising a first list of one or more identifiers of one or more services granted by the first registrar entity for the first application entity (20; 20'), wherein the second message further comprises a valid time, wherein the valid time indicates an effective time period for which the first service is provided to the device; sending, by the first application entity, AE, (20; 20'), a third message comprising a registration request for a second service of the oneM2M service layer to a second oneM2M common service entity,CSE, providing a second registrar entity; and receiving a fourth message that is responsive to the third message, the fourth message comprising a second list of one or more identifiers of one or more services granted by the second registrar entity for the first application entity (20; 20'); wherein the first application entity,AE, (20; 20') is simultaneously registered with the first registrar entity and the second registrar entity. sending, by a first application entity,AE, (20; 20') of the device, a first message comprising a registration request for a first service of a oneM2M service layer to a first oneM2M common service entity, CSE, providing a first registrar entity; receiving a second message that is responsive to the first message, the second message comprising a first list of one or more identifiers of one or more services granted by the first registrar entity for the first application entity (20; 20'), wherein the second message further comprises a valid time, wherein the valid time indicates an effective time period for which the first service is provided to the device; sending, by the first application entity, AE, (20; 20'), a third message comprising a registration request for a second service of the oneM2M service layer to a second oneM2M common service entity,CSE, providing a second registrar entity; and receiving a fourth message that is responsive to the third message, the fourth message comprising a second list of one or more identifiers of one or more services granted by the second registrar entity for the first application entity (20; 20'); wherein the first application entity,AE, (20; 20') is simultaneously registered with the first registrar entity and the second registrar entity.