Design of M2M Device Reachability Service Capability

Machine-to-Machine (M2M) communications allow networked devices to exchange information without human intervention. The large variety of devices with diverse characteristics has already resulted in vertical M2M applications based on very heterogeneous forms of platforms, technology, and data models. Interoperability is limited. In order to develop horizontal platforms across different business domains, networks and devices, it is necessary to outline generic capabilities. Service Capabilities provide data mediation functions that may be shared by different applications through application programming interfaces. REpresentational State Transfer (REST) architectural style is adopted for M2M communications. The paper presents an approach to design RESTful Web Services for access to location and presence status information of M2M devices. The Device Reachability Service Capability provides access to device location and allows device presence information to be registered and obtained. Web Service operations are identified by analysis on typical use cases. M2M device reachability information is modelled as REST resources organized in a tree structure. Web Service performance characteristics are evaluated by simulation. Key-Words: Machine-to-Machine communications, Service Capability, Web Services, Location, Presence status, Service Level Agreements