A Vertical Handoff Decision Algorithm Based on the Movement-Aware of Mobile Nodes

Currently, researchers introduce the dwell timer to reduce the ping-pang effect when they study the handover between heterogeneous networks. Simulations show that this kind of algorithms have a good effect in the case of that the terminal is in the coverage area of multiple access networks and does not leave away from the interactive network. However, if the terminal leaves away from the original network and needs to re-select a new network, the latency of those algorithms may lead to drop calls. Besides, when the terminal moves through the edge of the networks in a high speed, if the terminal select the WLAN access point it may result in frequent handovers because of its relative small coverage area. In this paper we propose a strategy based on movement-aware addressing the above problems. Our simulation results show that the strategy can make the terminal handover to the optimal network according to the users' preference timely and effectively and reduce the unnecessary handovers.

I. Introduction

In recent years, wireless networking technologies (such as LTE, WIMAX, WLAN, etc) have got rapid development. Every network has its own features and ability to provide services to adapt to the varied needs of individual users. For example, the LTE has low network latency, more extensive coverage, but it has high prices and low service rates; while though the WLAN has low prices and high service rates, it has larger latency and smaller coverage. When a terminal moves through the WLAN network in a high speed, it may result in frequency handovers. Therefore, we can see the necessity of using a variety of access networks to provide services for users. But facing the goal of providing services for users through the coexistence and collaborative work of wireless access networks, how can we achieve a seamless heterogeneous handover become one of the key technologies.