Research And Realization Of Traversal FW/NAT Based On UPnP

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. Multimedia communication become important work of communication field now, but there is problem that can't enter the internal network in the multimedia communication under the firewall . How realize the multimedia communication traverse Firewall/NAT 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. UPnP is an open standard based on TCP/IP protocol suite, it is independent of the network framework. UPnP offers great flexibility to construct networks and capacity of incorporating existing networks seamlessly. To overcome the problem of the multimedia communication, this article systemic study on the "Equipment finding and controlling" mechanism and "port mapping" mechanism offered by UPnP, and so on.At first, the operational principle of UPnP Protocol is analyzed in-depth and then is realized on linux. 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. Secondly, Propose a FW/NAT 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 and "port mapping" mechanism offered by UPnP. It's simple and convenient to realize, general and easy to use for...