Study And Implementation Of Key Technology For Ubiquitous Device Interconnect

With the development of computer and communication technology,more and more smart device and information-based consumer electronics come into our life. These devices make our life more comfortable, more convenient, and more efficient, but there are lots of differences in the standard which used in these devices. These stardands are put forward by different producers and organizations. There are many heterogeneous networks around us, this give rise to many problems in achieving resource sharing, service collaboration and systems integration. How to break these information barriers caused by heterogeneous networks is a urgent problem. At present,there have been some protocols which can achieve both seamless connection and interoperation of various devices in the digital home network. These protocols include UPnP, IGRS, Echonet, HAVi, iTopHome and OSGi, etc. Microsoft's UPnP and domestic IGRS have gradually become two mainstreams. How to realize interoperation, mutual discovery, resource sharing, and coordination of services of the protocols is necessary.According to what has been mentioned above, we know that these protocals are based on TCP/IP protocols. However, in most situations, we do not need too high transmission speed, we pay more attention to convenience and low power consumption and more energy efficiency. In this demand-driven situation, Zigbee, Bluetooth and other non-IP devices have been widely used. How to achieve seamless operation between IP devices and non-IP devices is an another question.In order to tackle the two problems above, a bridge which supports multiple protocols is needed. In respect of hardware, the bridge must have the capability of multiple accesses, it is free to choose means of wireless or wired for users. In respect of software, in order to complete sharing and collaboration of services from different network terminals of information, the bridge must support multiple protocols and help to achieve the conversion a these protocols.Based on requirements above, a bridge hardware which supports multiple network accesses is design. It can complete interconnection between varieties of network devices in physical. And then the protocols of UPnP, IGRS, Zigbee, Bluetooth are analysised and an unified interface that can make us easy to integrate these protocols is propesed. The interface is built on the basis of conversion of these protocols. This paper mainly describes the protocol conversion between Zigbee and UPnP. The conversion of other protocals is completed by others. Firstly, a careful analysis of the UPnP protocol and Zigbee protocol are made. In the Zigbee networks, Zigbee coordinator is necessary, which plays the part of creating the networks. The coordinator communicates with other devices and delivers all device descriptions to the bridge by UART. In order to complete the integration of the two protocols, the bridge receives all information of devices and then virtualize them as UPnP devices, so that other devices of UPnP control point can control Zigbee devices. Secondly, a test environment with two Zigbee devices are built. One of the devices plays as a lamp and the other plays as a temperature and humidity sensor. Thirdly, I analyze the search and control function (through a UPnP control point query temperature and humidity of sensor remotely and control the lights remotely). At last the conversion efficiency of the software bridge and the system performanceare estimated.