ITU-T Recommendation Q.3052 describes an overview of APIs and protocols for the M2M service layer and the related API and protocol requirements. It describes the component based M2M reference model, including the reference points of the M2M service layer. APIs and protocols for M2M are introduced, including existing APIs and protocols for M2M service layer and M2M protocol structure and stacks. Finally, general requirements of APIs and protocols with respect to the M2M service layer are described.