Decision algorithm and procedure for fast handover between 3G and WLAN

Abstract: Different types of wireless network systems have been developed to offer Internet access to mobile end users. Now days a burning issue is to provide the network facility to end users on anywhere and anytime bases. Typical examples of wireless networks are 3G and WLAN (wireless local area network). An important issue is to integrate these heterogeneous networks and manage the mobile nodes while moving across heterogeneous networks with session continuity, low latency for handover between networks that are based on different technologies (vertical handover) and minimum packet loss. To achieve this, it is important to find the right point in time to perform a handover between two networks and to find a new network that, in fact, improves the connectivity over a reasonable time span. In this thesis, we propose vertical handover techniques for mobile users, based on predictive and adaptive schemes for the selection of the next network. The handover decision between the technologies takes the velocity of the mobile node, battery condition of mobile node, signal to interference ratio (SIR), application requirements and received signal strength RSS) as decision parameters. In order to reduce unnecessary handover, the concept of dwell timer is used and to reduce the handover latency, the predictive mode of Fast Mobile IPv6 (FMIPv6) and for minimum packet loss, the concept of tunnelling and buffering of packets on new access router in advance are proposed.