A Scheme Improving Fast PMIPv6-based Network Mobility by Eliminating Tunneling Overload for ITS

NEtwork MObility Basic Support (NEMO BS) protocol has been investigated to provide Internet connectivity of a group of nodes, which is suitable for Intelligent Transportation Systems (ITS) applications. Since NEMO BS is based on Mobile IPv6 (MIPv6), it often increases traffic load and handover latency due to the handover procedure. Thus, schemes combining Proxy MIPv6 (PMIPv6) with NEMO (PNEMO) have emerged to solve these problems. However, they still suffer from packet loss and long handover latency during the handover. To prevent packet loss and reduce the handover latency, Fast P-NEMO (FP-NEMO) has emerged. Although FPNEMO accelerates the handover procedure through tunneling, it may cause a serious burden of the tunnel between Mobile Access Gateways (MAGs). This is because all packets destined for Mobile Network Nodes (MNNs) are forwarded to a New MAG (NMAG) through the tunnel between MAGs. This problem becomes more critical, as the number of MNNs is large and there exists heavy traffic between MAGs. Therefore, we propose a scheme Improving FP-NEMO (IFP-NEMO) to eliminate that tunneling burden. IFP-NEMO performs the registration prior to the layer 2 handover. When the registration is completed, packets are forwarded to the NMAG directly, so that the tunnel between MAGs is not used during the handover. IFP-NEMO is analyzed and compared with FP-NEMO through performance evaluations. We show that IFP-NEMO outperforms FP-NEMO in numerical results.