Research And Application Of Resource Model And Control Mechanism Based On WoT

With the development of Web technology and the improvement of the capabilities of IoT(Internet of Things)devices,the concept of WoT(Web of Things)is formed.In WoT,the device resource model is built to make devices as resources of Web and the existing Web technology is used to realize the control and management of resource access and unified data access.This thesis does research on the device resource model of IoT,access mechanism of device resource and it's data and so on based on Web technology and verifies them combined with specific IoT scenarios.The main content of this thesis is as follows:(1)In view of the problem that the resource path is not unique in the device resource description model and the resource can not be remotely accessed and controlled,this thesis divides resources into the static and the dynamic,and then the hierarchical structure model is respectively built.According to the model,the unique URI path can be mapped and API interfaces of resources can also be published accordingly.In order to verify the correctness of the model,a practical inspection which takes the temperature sensor and the parking lock as examples is carried out.The result shows that the model not only makes the device uniquely correspond with the resource,but also realizes the remote access and control by calling resource API interfaces.(2)Aimed at the problem of determining the legitimacy of device resources in the process of access,the original access control mechanism is improved in this thesis.Illegal device resources can be filtered by setting IP white list,assigning key and discriminating whether the key matches with the attribute or not.Then,the overall process of access control is given.At last,it is applied to the WoT gateway which is verified in several scenarios.The result shows that the mechanism can shield access of illegal device resources and also meet the needs of different access scenarios.(3)For the congestion problem in the access process,the model of device attribute priority based on analytic hierarchy process which specifically quantifies the weight of each attribute is proposed in this thesis.Then,the scene of smart home is taken as an example and the priority queue of five attributes of temperature,light,smoke,infrared and PM2.5 is solved.Finally,it is applied in the data access control of WoT.The result shows that the data packets can be received and processed in priority order,which alleviates the problem of congestion when large quantities of data are accessed,and also keeps important data being updated in time.(4)In order to improve the utilization of device resources and implement the function of the secure sharing of user's device resources,this thesis introduces the authority attribute on the basis of the attribute-based access control.Four attribute expressions of user,resource,environment and authority are respectively given and the process of device resource access control is also given based on it.At last,it is applied in the development of cloud platform of IoT and a functional test is also conducted.The result shows that the mechanism enables the secure sharing of applications and device resources between different users.