Enhanced Network Mobility Management for Vehicular Networks

Network mobility basic support (NEMO-BS) is able to maintain Internet connectivity among a set of mobile network nodes and, hence, has been considered as an intelligent transportation systems standard. However, NEMO-BS often results in unacceptably long handover latency and increased data loss to the vehicle. To address these issues, several schemes have employed a fast handover scheme by using Fast Proxy Mobile IPv6 (FPMIPv6) in NEMO-BS. Because these previous schemes are designed for a single vehicle, they have to establish the tunnel between the mobile access gateways (MAGs) for every single vehicle that moves to a new Internet protocol domain. Thus, these schemes may incur significant signaling overhead in vehicular networks (VNs), where vehicles have high mobility, and the number of vehicles is large. In this paper, we propose a group-based network mobility management scheme that also adopts the approach of FPMIPv6 to mitigate such signaling burden. Our proposed scheme establishes multiple tunnels at once for a group of moving vehicles by sending a single tunnel-establishment message to the next MAG. We also propose to pre-establish the tunnel by considering the geographic characteristics of VNs with the intent to reduce the handover latency. Using analytical models, we evaluate the performance of the proposed network mobility management scheme as compared with other previous schemes in terms of signaling cost, handover latency, and packet delivery cost. Our analytical study is verified by simulation results.