Using Predictive Triggers to Improve Handover Performance in Mixed Networks

End-users of multi-radio devices expect ubiquitous connectivity anytime and anywhere across heterogeneous networks. A minimal service disruption time while roaming across networks is key for successful deployments. Today's roaming decisions are reactive and traditionally based on thresholds for signal strength, missed beacons, or other properties, leading to undesirable handover delays. In this paper we propose a novel and energy efficient approach to predict when a device needs to take proactive actions to perform either a horizontal or vertical handover. The significant improvements our solution achieved in reducing service discontinuity time are demonstrated by applying our algorithms on WiFi and WiMax networks, in both enterprise and citywide wireless environments.