Route optimization enhancement schemes for MANEMO networks

Abstract

The increasing demand for global Internet connectivity has increased the demand for Network Mobility (NEMO). Internet Engineering Task Force (IETF) has introduced the NEMO Basic Support (NEMO BS) protocol to address the limitations of Mobile IPv6 (MIPv6) protocol to support the complete IP network, which is Mobile Router (MR) as an alternative of a single host. Under NEMO BS protocol, all data packet to/from Mobile Network Nodes (MNNs) must go through Bidirectional Tunnel (BT) that established between Mobile Router and its Home Agent (MR-HA). The Home Agent then encapsulates these packets and forwards them to the MR. The MR, in turn, decapsulates the packets and forwards them to the MNN. And thus, the suboptimal and inefficient routing path would be generated especially in Nested NEMO networks (Pinball problems). The difficulties associated with the packet delivery are, the packet overhead and the route delay which lead to the traffic congestion and then bottleneck links issues which are considered as Route Optimization (RO) and Multihoming concerns. Therefore, two schemes have been proposed. The first is for MANET for NEMO (MANEMO) Routing Optimization (RO), and the second proposed scheme is Multihoming of MANEMO. After that, the proposed MANEMO RO and Multihoming schemes are presented as (MROM) scheme. The proposed MROM scheme is a layer three solution to support RO and Multihoming for mobile networks. Firstly, the proposed MANEMO RO scheme comes as a complementing solution for the pinball problem, by avoiding the bidirectional MR-HA tunnel that optimizes the transmission of packets between an MNN/MR and a Corresponding Node/Home Agent (CN/HA). A discussion is presented about RO and Multihoming issues for Nested NEMO such as tunneling redundancy, HA dependency, processing delay, bottleneck, traffic congestion, ER selection, and scalability consideration in the design. In order to address suboptimal NEMO RO, this work utilizes NEMO Centric MANEMO (NCM) protocol in addition to Proxy Home Agent (PHA). Additionally, the thesis proposes the design to address Nested NEMO issues in a post disaster scenario by using PHA in the infrastructure and using Neighbor Discovery protocol (TDP/NINA) for communication localization. Thus, the signaling message flow and the algorithm are written to give the proposed scheme more flexibility. The existing NEMOBSP is capable of registering only a single primary Care of Address (CoA) of a MR during movement between different networks. Thus, when this link fails, a problem of network connectivity is created due to there is no secondary HA to keep a continuous Internet connectivity in NEMO. As a result, the proposed MROM applying a multihoming technique at any place, anywhere to provide uninterrupted Internet connection in NEMO has become a significant area of research. When a mobile network is multihomed, it is possible to achieve some features; namely, increased availability, balanced traffic load with flow distribution through simultaneous connectivity to access a router (Exit Router, ER). The research evaluation is done using analytical approach and simulation. In the analytical approach, the performance metrics are to be identified and evaluated. In the simulation approach, the Wireshark is used with NS-3 to generate the simulation results. The analytical result shows that the proposed scheme reduces average handoff cost by 64% lower compared to the NEMO-BSP and PNEMO. The simulation is done using Network Simulator version 3 (NS-3). The simulation result shows that the proposed scheme outperforms the standard NEMO BSP and P-NEMO in terms of packet loss (less than 1%) and handoff delay (average improvement by 76%). MROM routing scheme remains lower than NEMO BS by 42% to 67%. This is because proposed MROM scheme does not update all HAs for MRs handoffs (just PHA is updated and it transmits a copy of this update to other HAs), while NEMO Basic Support Protocol needs to update MN_HA and MR_HA for all handoff.