A MANEMO node is an IP-based mobile node that has interface attachments to both a mobile network, using Network Mobility (NEMO), and a Mobile Ad Hoc Network (MANET). While communicating with a correspondent node in the Internet, the MANEMO node should use the best possible path. Therefore, as conditions change, a handover between NEMO and MANET is desirable. This paper describes the operation of a MANEMO handover when IEEE 802.11 is used. An analytical model illustrates that packet loss during a MANEMO handover may severely affect data and real-time applications. We therefore propose using buffering during the handover, by making use of the Power Save Mode in IEEE 802.11. In the proposed algorithm, a MANEMO node may rapidly switch between the two interfaces, eventually receiving packets delivered via the old network interface while initiating the Mobile IP/NEMO handover on the new interface. Performance results show that packet loss can be significantly reduced, with small and acceptable increases in signalling overhead and end-to-end delay.

This paper proposes a protocol called vLIN6 which supports both network mobility and host mobility in IPv6. There are several proposals to support network mobility and host mobility. Network Mobility (NEMO) Basic Support Protocol has several problems such as pinball routing, large header overhead due to multiple levels of tunneling, and a single point of failure. Optimized NEMO (ONEMO) and Mobile IP with Address Translation (MAT) are solutions to provide route optimization, but they generate a lot of signaling messages at a handover. In vLIN6, packet relay is required only once regardless of the nested level in network mobility while optimal routing is always provided in host mobility. A fixed-sized extension header is used in network mobility while there is no header overhead in host mobility. vLIN6 is more tolerant of network failure and mobility agent failure than NEMO Basic Support Protocol. It also allows ordinary IPv6 nodes to communicate with mobile nodes and nodes in the mobile network. We implemented vLIN6 on NetBSD 2.0 Release. Our measurement results showed vLIN6 can provide host mobility and network mobility with low overhead.

To support multimedia applications effectively in mobile networks, the handover latency or packet losses during handover should be very small. Addressing this issue, we present a cooperative mobile router-based handover (CoMoRoHo) scheme for long-vehicular multihomed mobile networks. The basic idea behind CoMoRoHo is to enable different mobile routers to access different subnets during a handover and cooperatively receive packets destined for each other. In general, packet losses are directly proportional to handover latency; however, the overlapped reception of packets from different subnets makes possible to minimize packet losses even without reducing handover latency. To evaluate the scheme, we carried out performance modeling of the CoMoRoHo scheme in comparison with the Fast Handover for Mobile IPv6 (FMIPv6) protocol in regard to the handover latency, packet loss, signaling overhead, and packet delivery overhead in access networks. The analysis results show that CoMoRoHo outperforms FMIPv6 by reducing the packet losses as well as signaling overheads by more than 50%. Moreover, CoMoRoHo imposes lower packet delivery overheads required for preventing packets from being dropped from access routers. We thus conclude that CoMoRoHo is a scalable scheme because its performance remains intact even when the access network is overloaded.

Mobile IP is a solution to support mobile nodes but it does not handle NEtwork MObility (NEMO). The NEMO Basic Support (NBS) [1] ensures session continuity for all the nodes in a MObile NETwork (MONET). Since the protocol is based on Mobile IP, it inherits from Mobile IP the same fundamental problem such as tunnel convergence, when it is used to support the multicast for NEMO. In this paper, we propose the multicast Route Optimization (RO) scheme in NEMO environments. We suppose that the Mobile Router (MR) has a multicast function and the Nested Mobile Router Information (NeMRI). The NeMRI is used to record a list of the CoAs of all the MRs located below. And it obtains information whether the MRs desire multicast services. Also, we adopt any RO scheme to handle pinball routing. Therefore, we achieve optimal routes for multicasting in NEMO. We also develop analytic models to evaluate the performance of our scheme. We show much lower multicast tree delay and cost in NEMO compared with other techniques such as Bi-directional Tunneling (BT), Remote Subscription (RS), and Mobile Multicast (MoM) based on the NBS protocol.

The boundary of a distributed denial of service (DDoS) attack, one of the most threatening attacks in a wired network, now extends to wireless mobile networks, following the appearance of a DDoS attack tool targeted at mobile phones. However, the existing defense mechanisms against such attacks in a wired network are not effective in a wireless mobile network, because of differences in their characteristics such as the mobile possibility of attack agents. In this paper, we propose a proactive defense mechanism against IP spoofing traffic for mobile networks. IP spoofing is one of the features of a DDoS attack against which it is most difficult to defend. Among the various mobile networks, we focus on the Network Mobility standard that is being established by the NEMO Working Group in the IETF. Our defense consists of following five processes: speedy detection, filtering of attack packets, identification of attack agents, isolation of attack agents, and notification to neighboring routers. We simulated and analyzed the effects on normal traffic of moving attack agents, and the results of applying our defense to a mobile network. Our simulation results show that our mechanism provides a robust defense.

This paper proposes χLIN6-NEMO, a network mobility protocol based on LIN6. LIN6 is a host mobility protocol in IPv6 and is based on separation of the location and the identifier. In IETF, NEMO Basic Support Protocol based on Mobile IPv6 is standardized as a network mobility protocol. NEMO Basic Support Protocol as well as Mobile IPv6, however, has several fundamental problems in its communication procedures such as inefficient routing, header overhead due to tunneling, and single point of failure. χLIN6-NEMO makes use of the address structure of LIN6 and solves these problems. A fixed node and a Mobile IPv6 node can be connected to a mobile network provided by χLIN6-NEMO. A mobile network provided by NEMO Basic Support Protocol can also be connected to a mobile network provided by χLIN6-NEMO. We implemented χLIN6-NEMO on NetBSD 1.6.2 Release. Our measurement results showed χLIN6-NEMO can provide network mobility with low overhead.

This paper compared the approaches concerning the pinball routing problem that occurs in the nested network in network mobility environment and developed the analytic framework to model. Each model was evaluated of transmission latency, memory usage, and BU's occurrence number at routing optimization process. The estimation result showed that the optimization mechanism achievement overhead existed in each model, and the full optimization of the specific model was not attained because of it. Therefore, the most appropriate approach for routing optimization in nested NEMO can be determined only after a careful evaluation, and the proposals must consider using it in combination with other approaches. The modeling framework presented in this paper is intended to quantity the relative merits and demerits of the various approaches.