The Design and Realization for the Integration of Heterogeneous Networks

Abstract

The network communication recently becomes a part of human life. In order to provide users a more convenient communication environment, the study of integrating different networks also becomes an important research. This paper tries to integrate wired and wireless networks based on the concept of getting information everywhere and anywhere, static or moving. The integrated network is called 4GL (4G Like) network, which consists of Internet, PSTN, WLAN, and cellular phone system. In the integrated environment, Internet is considered as a backbone network. Each network has its own features. A mobile host with multiple adapters (Ethernet, WLAN adapter, cellular phone adapter) can seamlessly roam within the environment. The architecture of our system is based on that of GSM (Global System for Mobile communication) system. There are three layers in our model: HNIC (Heterogeneous Network Integration Center) layer, IG (Intelligent Gateway) layer and mobile device layer. HNIC is the highest layer, which is for the location management and the mobile control of devices; it provides enough functions for constructing a robust and seamless roaming environment. IG serves as a bridge between Internet and a mobile device; its function is kept simple, so that the work of integrating different networks into Internet becomes easier. Mobile device layer is for the user’s application. The integrated environment has the following features: (1) it is a robust seamless roaming environment; (2) both horizontal and vertical handoff are provided: (3) the adapter could be used interchangeable, i.e., their functions can compensate with each other. In the paper, the architecture of the system, the operational model, the design issues, the implementation, and the performance are described in detail. Finally, the contribution of the paper is given.