Design and implementation of service API for large-scale house log in smart city cloud

Smart city is a next-generation city planning. In the smart city, some value-added services such as energy saving and optimization of traffic are provided using wide variety of logs collected from various appliances and sensors. We are currently developing a smart city platform, called Scallop4SC, which supports collecting and processing the extremely large-scale log data. This system stores variety of logs on the HBase key-value store, and supports powerful data processing by Hadoop MapReduce. The goal of this paper is to propose service API of Scallop4SC. The API should be implemented as a Web service, which allows heterogeneous clients to access large-scale log (of energy, device and environment), as well as house configuration data of the smart city. In order to cover queries from a variety of applications, we design possible combinations of service type, data type, access type and queries, based on practical service scenarios. As a case study, we present concrete smart city services for energy saving and quality of life improvement. Then, we evaluate how the proposed API can implement these practical services.