Optimizing Media Independent Handover Using Predictive Geographical Information for Vehicular Based Systems

摘要

Media Independent Handover (MIH) is an emerging standard for handover across heterogeneous networks. It proposes to communicate network critical events to upper layer mobility protocols. Within MIH a Link_Going_Down (LGD) event is intended to provide predictive indications of network failure. We illustrate a scenario in which the indications provided by the LGD event are not sufficiently proactive to enable the necessary link configurations prior to network failure. In this paper we propose an alternative approach in which a new Predictive_Link_Going_Down (PLGD) event is implemented. Our PLGD event uses geographical maps to predict vehicle movements, thereby accurately estimating the point of network performance degradation. Such an approach enables the upper layer mobility protocol to provide preconfigured alternate paths enabling soft handover. In order to trigger our PLGD event we have created a mathematic model which uses the vehicles position and velocity as well as the neighbourhood Base Stations (BS) geographical information. Results presented illustrate that our approach significantly reduces the handover duration thereby enhancing handover performance in comparison to the standard MIH approach.