Research And Implementation Of Smart Home System Based On Software Definition And Context Awareness

Since China has entered an aging society,the supporting issue has become the focus of government and society.The community supporting scheme is combining the supporting scheme provided by agency with the supporting scheme provided by family which is a new way to solve the supporting issue.In the community supporting scenario,constructing a smart home system for the elder could provide a convenient,comfortable,safely and energy-saving living environment.There are two major problems in the current smart home system.The first problem is the heterogeneity issue of devices and data.Since the smart home industry does not form a unified standard,the smart devices from different companies were isolated and incompatible.So it is hard to sharing information as well as coordinating with each other.The second problem is context awareness.The current smart home solutions do not realize the real intelligent.They can't perceive the need of users,and provide appropriate services.In this paper,we focus on these problems,and propose a smart home system based on software definition and context awareness.The main works are as follows:Firstly,to solve the heterogeneous problem of devices,we studied the system architecture of smart home.This paper studied the smart home system architecture based on Web of Things.It abstracts the heterogeneous devices as Web resources,and implements the interoperability of device by this way.However,this architecture can't adapt to the rapid change of user needs.Based on the idea of software defined network that separate the control plane and the data plane,this paper presents a smart home system architecture based on software definition.In addition,this paper studies the characteristics of the traffic of the Internet of things under the SDN,and proposes an improved flow table pre-installation mechanism,which can decrease the mismatch flows and reduce the transmission delay for Internet of Things devices.Finally,we analyzed the advantages of software defined smart home.Secondly,to solve the problem of context awareness in smart home,we studied the context aware system based on rule reasoning.We analyzed the field knowledge of smart home,and construct the domain ontologies model of smart home.We annotated the bottom layer data such as sensors data and device states by semantic method.We input the context information and the inference rules to the rule reasoning engine,after that we can get the high-level context information as well as the device control schemes.Finally,the service invocation module invokes the device functions according to the control scheme to meet the user's requirements.Finally,based on the research above,we design a smart home system prototype based on software definition and context awareness.We tested this prototype,by verified the effectiveness of software defined smart home architecture and verified that smart home system has the ability of context aware and services providing.