The Republic of Macedonia

The vertical handover decision strategy in the heterogeneous wireless networks is very challenging issue because it needs to deal with many different radio access networks and make decisions for vertical handover calls between them. Due to traffic offloading the decisions for vertical handovers to WLAN hotspots in heterogeneous wireless networks are very important because they impact the QoS of the mobile users, especially when they are using real-time services. In this paper we propose vertical handover decision algorithm from WiMAX to WLAN networks based on the user’s speed and session’s priority (non-real-time or real-time service) of the mobile nodes. We use the IEEE 802.21 standard as a layout for implementing the algorithm. The implementation of our handover algorithm avoids unnecessary vertical handover from WiMAX to WLAN in scenarios with various traffic types and speeds of the mobile nodes. The results show that the proposed algorithm improves the vertical handover latency, packet loss and average throughput of the mobile users.