Utility-based load balancing in WLAN/UMTS internetworking systems

The complementary characteristics of 3 G cellular networks (such as UMTS) and IEEE´s 802.11 wireless LANs (WLANs) have stimulated intensive research efforts to integrate UMTS and WLAN networks. In such integrated networks, a mobile station is able to switch between UMTS and WLAN networks based on various network parameters such as network throughput, packet delay and other network or user quality criteria. In this paper, we develop a utility-based access selection algorithm targeted to achieve load balancing between UMTS and WLAN networks. The performance of our algorithm is evaluated using OPNET with dual-mode mobile stations.