Seamless handoff scheme for real-time application in the wireless IPv6 networking

Network Mobility (NEMO), derived from Mobile Internet Protocol version 6 (MIPv6) technology, has been evolving and expanding in very rapidity manner across very short period of time. In MIPv6 technology, the Access Router (AR) plays important roles such as provide sessions connectivity and safe-guarding communications protocol. Whereas in NEMO, the routers in the communication chains are essentially the moving targets and hence the Mobile Router (MR). The MR too, inherits the basic functionalities of AR. In the basic MIPv6 and NEMO modus operandi, when the Mobile Network Notes (MNN) roamed away from home link and attached to some other foreign link, the MNNs are also addressable via a secondary address named as Care-of Address (CoA). The MNN essentially registered its primary CoA to the router on its own home link and thus registering the router to be its Home Agent (HA). These communication sets, and the ingredients of the communication will be managed via Binding Updates (BU) and the Binding Acknowledgement (BAck). Since the NEMO is using MIPv6 as the backbone, NEMO also inevitably inherits many design difficulties and problems that the MIPv6 seen. Such as using the Internet Protocol Security (IPSec) with end-to-end tunneling and using nonce value within the BU to serve as part of the authentication process and many more. In this paper, we illustrate the scenario of authentication problems involving NEMO movements and the flaw in security design. With the aim of succeeding IPSec we then propose a much better solution which is the use of Random Number, coupled with PKI concept.

In this paper, a new approach is proposed to reduce handoff operation in IEEE 802.16e network. Traditional mobile approaches, such as mobile IPv6 (MIPv6) and hierarchical MIPv6 (HMIPv6), can support smoothly handoff. These approach, ,unfortunately, suffer large handoff delay and packet lost in macro mobility for mobile users. With the aid of the partner node, DAD operation can be pre-executed by the partner node before the mobile node initialize the handoff request, we propose a cross-layer partner based fast handoff mechanism based on HMIPv6 in IEEE 802.16e network, called as P_HMIPv6 protocol. The P_HMIPv6 protocol is a cross-layer, layer 2 and layer 3, approach. The partner station (PS), which is a new component with relay ability and adopted by our protocol, is a static mobile station (MS). With the aid of the PSs, care-of address (CoA) can be pre-acquired and DAD operation can be pre-executed by the PS before the MS initials the layer 2 handoff. The simulation results show that P_HMIPv6 protocol actually achieves the performance improvements in the handoff delay time and the packet loss.

The concept of care-of-address (CoA) is a major cause of excessive handoff delay in Mobile IPv6 for real time multimedia traffic. Many schemes eliminate the use of CoA at the micro-mobility scale, but leave the macro-mobility unsolved. This paper proposes a novel alternative IPv6 mobility scheme based on universal addressing - Cellular Universal IP (CUIP) - for real-time traffic in wireless access networks. In CUIP, a mobile node is addressed with a universal IP address regardless of its location, making CoA and tunneling unnecessary in micromobility and even macromobility handoffs. CUIP manages roaming and handoff differently - whereas explicit signaling is used for roaming, a handoff-on-the-fly route-update scheme is used during handoff to embed signaling information into the outgoing data packets to minimize handoff delay. We prove analytically that, on average, fewer than three routers need to be updated per handoff. As a result, CUIP incurs an expected network layer handoff delay on the order of milliseconds only. In addition, the support of QoS is possible. A simple security scheme is also proposed to enable mutual authentication at the network layer.

An enhanced fast handover with seamless mobility support for next-generation wireless networks

Fast handover protocol provides seamless handover in mobile IPv6 networks by reducing handover latency. One assumption in fast handover is that the MN (Mobile Node) or the network could know or predict the new AR (Access Router) before data transport from the previous AR to the MN is disrupted. In order to achieve this capability, the complexity of predicting the new AR and the diversity of the wireless link technologies should be considered. While it is difficult to know or predict the new AR exactly, a better solution is required to find a reasonable set of candidate ARs (i.e., neighbor ARs) that are likely to be the new AR after a handover. This paper introduces a solution to support a fast handover mechanism using multi-tunnels between MAP (Mobility Anchor Point) and neighbor ARs in HMIPv6 (Hierarchical Mobile IPv6) network. It includes the concepts of Proxy Mobile IP for creation of CoA (Care of Address) and DAD (Duplicate Address Detection). In this protocol, the MN can handover without receiving any information about the new AR and this eliminates difficulties to know or predict exactly the new AR which is not specified in standard fast handover scheme. It decouples layer-2 and layer-3 handover and efficiently reduces handover latency through the minimized number of wireless signaling messages and pre-DAD. It also saves periods of service disruption and prevents packet loss in the case of ping-pong movement of the high-speed MN. The performance of the proposed mechanism is evaluated by simulations under variable conditions.

A DNS-assisted Simultaneous Mobility Support Procedure for Mobile IPv6

H.264/SVC vs. H.264/AVC video quality comparison under QoE-driven seamless handoff

Due to the proliferation of handheld mobile devices, multimedia applications like Voice over IP (VoIP), video conferencing, network music, and online gaming are gaining popularity in recent years. These applications are well known to be delay sensitive and resource demanding. The mobility of mobile devices, running these applications, across different networks causes delay and service disruption. Mobile IPv6 was proposed to provide mobility support to IPv6-based mobile nodes for continuous communication when they roam across different networks. However, the Route Optimization procedure in Mobile IPv6 involves the verification of mobile node's reachability at the home address and at the care-of address (home test and care-of test) that results in higher handover delays and signalling overhead. This paper presents an enhanced procedure, time-based one-time password Route Optimization (TOTP-RO), for Mobile IPv6 Route Optimization that uses the concepts of shared secret Token, time based one-time password (TOTP) along with verification of the mobile node via direct communication and maintaining the status of correspondent node's compatibility. The TOTP-RO was implemented in network simulator (NS-2) and an analytical analysis was also made. Analysis showed that TOTP-RO has lower handover delays, packet loss, and signalling overhead with an increased level of security as compared to the standard Mobile IPv6's Return-Routability-based Route Optimization (RR-RO).

Mobility management is a key issue to achieve uninterrupted Internet services in IP based network. In IPv6, the mobility management is realized by its mobile version namely the Mobile IPv6 (MIPv6). The MIPv6 is further extended to Hierarchical MIPv6 (HMIPv6) to reduce handoff latency suffered by mobile nodes and signaling load incurred due to movement if nodes within the micro mobility region defined by HMIPv6. The HMIPv6 is considered as first widely accepted layered architecture for mobility management for IPv6 network. Influenced by the benefits of HMIPv6, many researchers have suggested extension of MIPv6 into multiple layers. However, there is very little work on finding optimal levels of hierarchy in such layered architecture. The focus of this paper is to evaluate the performance of a multilayer (N-layered with N as 5) MIPv6 architecture through experimental testbed. We have observed handoff latency, signaling overhead and tunneling cost and figured out the optimal levels of hierarchy that provides the best acceptable results for all the observed parameters. Since, HMIPv6 outperforms MIPv6 in terms of handoff latency and signaling cost, so we compare our results with HMIPv6. Testbed observation depicts that three levels of hierarchy in MIPv6 architecture provides optimal performance with 27 % reduction in handoff latency and 67 % reduction in signaling overhead compared to single layer architecture like Hierarchical MIPv6 (HMIPv6) protocol.

The route optimization operation in Mobile IP Version 6 (MIPv6) allows direct routing from any correspondent node to any mobile node and thus eliminates the problem of "triangle routing" present in the base Mobile IP Version 4 (MIPv4) protocol. Route optimization, however, requires that a mobile node constantly inform its correspondent nodes about its new care-of addresses by sending them binding update messages. Unauthenticated or malicious binding updates open the door for intruders to perform redirect attacks, i.e., malicious acts which redirect traffic from correspondent nodes to locations chosen by intruders. How to protect binding update messages to defend against redirect attacks is a challenging problem given the open environment in which MIPv6 operates. In this paper, we first look at two solutions proposed by the IETF Mobile IP Working Group and point out their weaknesses. We then present a new protocol for securing binding update messages. We also show that our protocol achieves strong security and at the same time is highly scalable to wide spread deployment.

With the functionalities of obtaining new care-of-address (CoA) ahead and building tunnels for packet forwarding during handover, the fast handover scheme has better performance than Mobile IPv6. However, the handover performance is downgraded if mobile node (MN) cannot finish the handover preparation before the associated link is broken. In this paper, we propose an optimistic ready-tunneling (ORT) control scheme to resolve the aforementioned problems. In the proposed ORT scheme, new access router (NAR) can prepare for a new CoA and builds a tunnel for MN ahead when MN enters the domain of NAR. As a result, MN can switch to the new network domain smoothly because of early CoA acquisition and tunnel establishment during handover.

Mobile communications services have become an integral part of everyone's life mainly by facilities provided in the exchange of information for mobile users independent of time, location, or access arrangement. In this context, the mobility management with seamless handover is crucial to provide rich communication services to mobile users. Mobile IPv4 (MIPv4) and IPv6 (MIPv6) and its extensions were proposed by IETF for IP layer mobility management. Nowadays, most access networks run IPv4 as its network protocol. However, IPv6 usage is moving forward and mechanisms are required to ensure mobility management and roaming between IPv4 and IPv6 access networks. In this paper, we analyze the performance of Dual Stack Mobile IPv6 (DSMIPv6) when the mobile node is roaming to different IPv4 and IPv6 networks. We investigate the signaling procedures and messages format under different handoff scenarios to derive the mobility management signaling cost. We propose an analytical model that is capable to derive the signaling cost overhead, disruption time latency and average packet loss based on node mobility and user traffic patterns. Numerical results are also presented to better understand the system performance under different traffic and mobility scenarios. From the analysis derived in this work it is possible to better understand the performance of DSMIPv6 and identify the signaling overhead under different roaming scenarios.

Guaranteeing the quality of service (QoS) for real time applications is one of the challenging issues in next generation all-IP networks. Analysing the user perceived throughput is essential to measure the QoS experienced by real time applications. Medium access control (MAC) mechanism of the serving access network as well as the vertical handover (VHO) algorithm used by the mobile terminals (MTs) for target network selection have significant impact on user perceived throughput. Apart from that the upper layer mobility management protocol also influences the throughput performance considerably. The existing frameworks for throughput analysis do not adequately address the MAC specific issues. In this work, we have developed an analytical framework to analyse user perceived throughput considering the effect of both MAC specific details and upper layer mobility management protocol. Using our proposed framework, we have compared the throughput performance of video traffic application when mobile IPv6 (MIPv6) and seamless IP diversity based generalized mobility architecture (SIGMA) are used for mobility management. Our analysis reveals that the superiority of SIGMA over MIPv6 is actually conditional on the performance of the underlying VHO algorithm. Extensive simulations have been done to validate the analytical results.

The current deployment of wireless mesh networks requires mobility management to track the current locations of mobile nodes around the network without service interruption. To do so, the Hierarchical Mobile IPv6 protocol has been chosen, which minimises the required signalling by introducing a new entity called the mobile anchor point to act as a local home agent for all visiting mobile nodes in a specific domain. It allows a mobile node to register its local/regional care-of addresses with a mobile anchor point by sending a local binding update message. However, the local binding update is quite sensitive; it modifies the routing to enable mobility in the wireless mesh networks. When a local binding update message is spoofed, an attacker can redirect traffic that is destined for legitimate mobile node either to itself or to another node. This situation leads to an increased risk of attacks. Therefore, this paper contributes to addressing this security issue based on wireless mesh networks by cryptography generation and verification of a mobile node’s local and regional care-of addresses, as well as the application of a novel method to verify the reachability of mobile node at claimed local care-of address. This is called the enhanced mobile anchor point registration protocol. The Scyther tool has been used to ensure the proposed protocol accuracy. Furthermore, the performance, in terms of the mobile anchor point registration delay and signalling overhead, is evaluated by using the OPNET modeller simulator.

Mobile IPv6 is a network-layer mobility protocol for the IPv6 Internet. The protocol includes several security mechanisms, such as the return-routability tests for the mobile’s home address and care-of addresses. This paper explains the threat model and design principles that motivated the Mobile IPv6 security features. While many of the ideas have become parts of the standard toolkit for designing Internet mobility protocols, some details of the reasoning have not been previously documented.