Research On UPnP Protocol And Its Application In Embedded Communication System

With the swift development of computer network and communication technology, small business and family network has become a new focus of the communication field. Although the scale of this kind of network is small, it does have bright prospect. How to realize the interconnection across various intellectual equipments existing extensively in the small business and family network is the key point.UPnP (Universal Plug and Play) Protocol was put forward by Microsoft to provide capacity of interconnection across various intellectual equipments existing extensively in the small business and family network. It is a simple, direct and easy technology which is high-efficient, flexible and standard complianted. By this technology, users do not need to understand any professional knowledge disposed about equipments. This can really accomplish "plug and play". In addition, because UPnP is an open standard based on TCP/IP protocol suite, it is independent of the network framework, such as Ethernet, Wi-Fi or 802.1 IB wireless network, IEEE 1394, telephone wire network or the power line network. UPnP offers great flexibility to construct networks and capacity of incorporating existing networks seamlessly. For these advantages, UPnP Protocol has been one of the major industry standards for constructing future digital family. It also pregnants with the enormous market, but the research in this respect is in the initial stage in our country.UPnP Protocol is in-depth analysised firstly in this paper and its application inembedded communication system is studied. The groundwork of this paper is as follows:1) Finish the disposition of the embedded operating system uClinux special to the target platform, this contributes to saving valuable hardware resources in embedded system and reduce the system cost.2) Realize the MTD driver to the flash chip on target board. By constructing readable and writable file system upnon the MTD driver, dynamic data in the embedded system can be permanently saved conveniently.3) UPnP Protocol is analyzed in-depth and then is realized on uClinux. Through utilizing the advantage of the open source code and doing some modifications special to the target platform, the quality and efficiency of the development are greatly improved.4) Propose a NAT/FW traversal solution to the multimedia communication based on IP of the small business and family network application scene. This scheme has utilized "Equipment finding and controlling" mechanism offered by UPnP. It's simple and convenient to realize, general and easy to use for End-Users.5) Design and realize a gateway equipment program uC-UPnP IGD which provides the support of UPnP Protocol for the target platform, it's the key point of NAT/FW Traversal solution putting forward in this paper. uC-UPnP IGD is designed as an indepedent module in target system, the low coupling degree improves system expansibility and maintainability, reduces the complexity of development at the same time. In addition, in order to guarantee the efficiency of the procedure, multi-thread and callback technique are used in design of uC-UPnP IGD. According to the experience and lessons during development, the framework of writing a UPnP equipment is summarized finally which has great reference value in developping other UPnP equipments.