Future generations of wireless networks will place great demands on the performance of radio access technology and the real-time multimedia applications provided by these new wireless environments. During the mobility between heterogeneous wireless networks, the quality of multimedia services for users depends heavily on seamless handover which should be provided by the middleware of IP to MAC protocol stack. IEEE 802.21 is designed for this reason which provided the basic platform for seamless handover between heterogeneous wireless networks. In this paper, a dynamically adjusted buffer component with algorithm for prediction of the buffer size is proposed to enhance the functionality of IEEE 802.21. The mechanism of proposed scheme included Service Specific Layer which decides the opportunity of handover, and adjusted Buffer which stores the temporal streaming data for applications between handover. The services and communication flows among service specific layer, buffer and IEEE 802.21 Media Independent Handover function are described and analyzed. According to analysis of the connection process and simulation, buffer prediction and pre-allocation could indeed reduce the influence of handover between heterogeneous wireless networks.
the International Conference on information Networking (ICOIN2008), 韓國釜山