Date Added: Jan 2010
A variety of wireless network technologies have been developed and deployed, including GSM/GPRS, UMTS, and WLAN. The advantages of having an integrated heterogeneous communication environment would be service convergence, joint resource management and adaptive quality of service. In such environment, operators would not need to reject the user requests, but redirect them to appropriate networks. However, the sought aims of a heterogeneous wireless system still have many pending issues. One is the selection of the most appropriate radio access technology according to the requested service and the context information about the user and the networks.