Home Devices Mediation using ontology alignment and code generation techniques
Charbel El Kaed · 2012
Ubiquitous systems imagined by Mark Weiser are emerging thanks to the development of embedded systems and plug-n-play protocols like the Universal Plug aNd Play (UPnP), the Intelligent Grouping and Resource Sharing (IGRS), the Device Pro le for Web Services (DPWS) and Apple Bonjour. Such protocols follow the service oriented architecture (SOA) paradigm and allow an automatic device and service discovery in a home network. Once devices are connected to the local network, applications deployed for example on a smart phone, a PC or a home gateway, discover the plug-n-play devices and act as control points. The aim of such applications is to orchestrate the interactions between the devices such as lights, TVs and printers, and their corresponding hosted services to accomplish a specific human daily task like printing a document or dimming a light. Devices supporting a plug-n-play protocol announce their hosted services each in its own description format and data content. Even similar devices supporting the same services represent their capabilities in a different representation format and content. Such heterogeneity along with the protocols layers diversity, prevent applications to use any available equivalent device on the network to accomplish a specific task. For instance, a UPnP printing application cannot interacts with an available DPWS printer on the network to print a document. Designing applications to support multiple protocols is time consuming since developers must implement the interaction with each device pro le and its own data description. Additionally, the deployed application must use multiple protocols stacks to interact with the device. More over, application vendors and telecoms operators need to orchestrate devices through a common application layer, independently from the protocol layers and the device description. To accomplish interoperability between plug-n-play devices and applications, we propose a generic approach which consists in automatically generating proxies based on an ontology alignment. The alignment contains the correspondences between two equivalent devices descriptions. Such correspondences actually represent the proxy behaviour which is used to provide interoperability between an application and a plug and play device. For instance, the generated proxy will announce itself on the network as a UPnP standard printer and will control the DPWS printer. Consequently, the UPnP printing application will interact transparently with the generated proxy which adapts and transfers the invocations to the real DPWS printer. We implemented a prototype as a proof of concept that we evaluated on several real UPnP and DPWS equivalent devices.