MIPv6 Experimental Evaluation using Overlay Networks

The commercial deployment of Mobile IPv6 has been hastened by the concepts of Integrated Wireless Networks and Overlay Networks, which are present in the notion of the forthcoming generation of wireless communications. Individual wireless access networks show limitations that can be overcome through the integration of different technologies into a single unified platform (i.e., 4G systems). This paper summarises practical experiments performed to evaluate the impact of inter-networking (i.e. vertical handovers) on the Network and Transport layers. Based on our observations, we propose and evaluate a number of inter-technology handover optimisation techniques, e.g., Router Advertisements frequency values, Binding Update simulcasting, Router Advertisement caching, and Soft Handovers. The paper concludes with the description of a policy-based mobility support middleware (PROTON) that hides 4G networking complexities from mobile users, provides informed handover-related decisions, and enables the application of different vertical handover methods and optimisations according to context.Publicad

Mobile IP movement detection optimisations in 802.11 wireless LANs

The IEEE 802.11 standard was developed to support the establishment of highly flexible wireless local area networks (wireless LANs). However, when an 802.11 mobile node moves from a wireless LAN on one IP network to a wireless LAN on a different network, an IP layer handoff occurs. During the handoff, the mobile node's IP settings must be updated in order to re-establish its IP connectivity at the new point of attachment. The Mobile IP protocol allows a mobile node to perform an IP handoff without breaking its active upper-layer sessions. Unfortunately, these handoffs introduce large latencies into a mobile node's traffic, during which packets are lost. As a result, the mobile node's upper-layer sessions and applications suffer significant disruptions due to this handoff latency. One of the main components of a Mobile IP handoff is the movement detection process, whereby a mobile node senses that it is attached to a new IP network. This procedure contributes significantly to the total Mobile IP handover latency and resulting disruption. This study investigates different mechanisms that aim to lower movement detection delays and thereby improve Mobile IP performance. These mechanisms are considered specifically within the context of 802.11 wireless LANs. In general, a mobile node detects attachment to a new network when a periodic IP level broadcast (advertisement) is received from that network. It will be shown that the elimination of this dependence on periodic advertisements, and the reliance instead on external information from the 802.11 link layer, results in both faster and more efficient movement detection. Furthermore, a hybrid system is proposed that incorporates several techniques to ensure that movement detection performs reliably within a variety of different network configurations. An evaluation framework is designed and implemented that supports the assessment of a wide range of movement detection mechanisms. This test bed allows Mobile IP handoffs to be analysed in detail, with specific focus on the movement detection process. The performance of several movement detection optimisations is compared using handoff latency and packet loss as metrics. The evaluation framework also supports real-time Voice over IP (VoIP) traffic. This is used to ascertain the effects that different movement detection techniques have on the output voice quality. These evaluations not only provide a quantitative performance analysis of these movement detection mechanisms, but also a qualitative assessment based on a VoIP application

Mobile Networking

We point out the different performance problems that need to be addressed when considering mobility in IP networks. We also define the reference architecture and present a framework to classify the different solutions for mobility management in IP networks. The performance of the major candidate micro-mobility solutions is evaluated for both real-time (UDP) and data (TCP) traffic through simulation and by means of an analytical model. Using these models we compare the performance of different mobility management schemes for different data and real-time services and the network resources that are needed for it. We point out the problems of TCP in wireless environments and review some proposed enhancements to TCP that aim at improving TCP performance. We make a detailed study of how some of micro-mobility protocols namely Cellular IP, Hawaii and Hierarchical Mobile IP affect the behavior of TCP and their interaction with the MAC layer. We investigate the impact of handoffs on TCP by means of simulation traces that show the evolution of segments and acknowledgments during handoffs.Publicad

Virtual Mobility Domains - A Mobility Architecture for the Future Internet

The advances in hardware and wireless technologies have made mobile communication devices affordable by a vast user community. With the advent of rich multimedia and social networking content, an influx of myriads of applications, and Internet supported services, there is an increasing user demand for the Internet connectivity anywhere and anytime. Mobility management is thus a crucial requirement for the Internet today. This work targets novel mobility management techniques, designed to work with the Floating Cloud Tiered (FCT) internetworking model, proposed for a future Internet. We derive the FCT internetworking model from the tiered structure existing among Internet Service Provider (ISP) networks, to define their business and peering relationships. In our novel mobility management scheme, we define Virtual Mobility Domains (VMDs) of various scopes, that can support both intra and inter-domain roaming using a single address for a mobile node. The scheme is network based and hence imposes no operational load on the mobile node. This scheme is the first of its kind, by leveraging the tiered structure and its hierarchical properties, the collaborative network-based mobility management mechanism, and the inheritance information in the tiered addresses to route packets. The contributions of this PhD thesis can be summarized as follows: · We contribute to the literature with a comprehensive analysis of the future Internet architectures and mobility protocols over the period of 2002-2012, in light of their identity and handoff management schemes. We present a qualitative evaluation of current and future schemes on a unified platform. · We design and implement a novel user-centric future Internet mobility architecture called Virtual Mobility Domain. VMD proposes a seamless, network-based, unique collaborative mobility management within/across ASes and ISPs in the FCT Internetworking model. The analytical and simulation-based handoff performance analysis of the VMD architecture in comparison with the IPv6-based mobility protocols presents the considerable performance improvements achieved by the VMD architecture. · We present a novel and user-centric handoff cost framework to analyze handoff performance of different mobility schemes. The framework helps to examine the impacts of registration costs, signaling overhead, and data loss for Internet connected mobile users employing a unified cost metric. We analyze the effect of each parameter in the handoff cost framework on the handoff cost components. We also compare the handoff performance of IPv6-based mobility protocols to the VMD. · We present a handoff cost optimization problem and analysis of its characteristics. We consider a mobility user as the primary focus of our study. We then identify the suitable mathematical methods that can be leveraged to solve the problem. We model the handoff cost problem in an optimization tool. We also conduct a mobility study - best of our knowledge, first of its kind - on providing a guide for finding the number of handoffs in a typical VMD for any given user\u27s mobility model. Plugging the output of mobility study, we then conduct a numerical analysis to find out optimum VMD for a given user mobility model and check if the theoretical inferences are in agreement with the output of the optimization tool

Adaptive Mobility Management Scheme for Mobile IP using Ad Hoc Networks.

Mobile IP has been developed to handle global mobility of mobile hosts. Mobile IP suffers from a number of drawbacks such as frequent location update, high signaling overhead, high handover latency, high packet loss rate, and requirement of infrastructure change. To treat these problems, we propose a new mobility management scheme by constructing dynamic service regions of Ad Hoc networks for roaming mobile host without location update to reduce signaling overhead and packets loss. Analytical analysis and simulation results are shown in this paper to demonstrate that the proposed scheme performs better performance than other schemes

Safetynet version 2, a packet error recovery architecture for vertical handoffs

Mobile devices are connecting to the Internet through an increasingly heterogeneous network environment. This connectivity via multiple types of wireless networks allows the mobile devices to take advantage of the high speed and the low cost of wireless local area networks and the large coverage of wireless wide area networks. To maximize the benefits from these complementing characteristics, the mobile devices need to be able to switch seamlessly between the different network types. However, the switch between the technologies, also known as a vertical handoff, often results in significant packet loss and degradation of connectivity due to handoff delay and also increased packet loss rate on the border of the coverage area of the networks. In our previous work, we have proposed an inter technology mobility management architecture which addresses the packet losses using selective resending of packets lost during the handoff period. In this paper, we extend the architecture to address packet losses due to wireless errors more efficiently by taking advantage of erasure codes to form redundancy packets. We propose to send these redundancy packets over both links. We show that this proposal reduces both the chances of packet loss and the buffering requirements of the original Safetynet scheme

A Framework of Cooperating Agents Hierarchies for Local-Area Mobility Support

Host mobility creates a routing problem in the Internet, where an IP address reflects the network\u27s point of attachment. Mobile IP, relying on a mapping between a home address and a care-of address, and a home registration process, is widely accepted as a solution for the host mobility problem in wide-area mobility scenarios. However, its home registration requirement, upon each change of point of attachment, makes it unsuitable to handle local-area mobility, resulting in large handoff latencies, increased packet loss, and disrupted services. In this dissertation, we introduce a local-area mobility support framework for IPv4 based on the deployment of multiple cooperating mobility agents hierarchies in the foreign domain. First, we introduce a hierarchy model offering a backward compatible mode to service legacy mobile hosts, unaware of local-area mobility extensions. Second, for intra-hierarchy handoffs, we identify several design deficiencies within the current Mobile IP hierarchy extension proposal, and present an enhanced regional registration framework for local handoffs that encompasses a replay protection identification value dissemination mechanism. In addition, we present two novel registration frameworks for home registrations involving local handoffs, in which we identify the dual nature of such registrations, and attempt to emphasize the local handoff aspect. One technique, maintains tunneling of data packets to the MH (Mobile Host) through an old path until a home registration reply is received to set up the new path. In contrast, the other technique adopts a more proactive bold approach in switching immediately to the new path resulting in a reduction of the handoff latency. Third, for inter-hierarchy handoffs, we present a scalable, configurable, and cooperation based framework between mobility agents hierarchies to reduce the handoffs latencies. An attempt is made to exploit the expected network proximity between hierarchies within the foreign domain, and maintain a mobile host\u27s home-registered care-of address unchanged while within the same foreign domain. In addition, the involved registration signaling design requires a reduced number of security associations between mobility agents belonging to different hierarchies, and copes with the fact that the mobile host\u27s home-registered care-of address might not be reachable

Minimization of Handoff Failure Probability for Next-Generation Wireless Systems

During the past few years, advances in mobile communication theory have enabled the development and deployment of different wireless technologies, complementary to each other. Hence, their integration can realize a unified wireless system that has the best features of the individual networks. Next-Generation Wireless Systems (NGWS) integrate different wireless systems, each of which is optimized for some specific services and coverage area to provide ubiquitous communications to the mobile users. In this paper, we propose to enhance the handoff performance of mobile IP in wireless IP networks by reducing the false handoff probability in the NGWS handoff management protocol. Based on the information of false handoff probability, we analyze its effect on mobile speed and handoff signaling delay.Comment: 16 Page

SD-MCAN: A Software-Defined Solution for IP Mobility in Campus Area Networks

Campus Area Networks (CANs) are a subset of enterprise networks, comprised of a network core connecting multiple Local Area Networks (LANs) across a college campus. Traditionally, hosts connect to the CAN via a single point of attachment; however, the past decade has seen the employment of mobile computing rise dramatically. Mobile devices must obtain new Internet Protocol (IP) addresses at each LAN as they migrate, wasting address space and disrupting host services. To prevent these issues, modern CANs should support IP mobility: allowing devices to keep a single IP address as they migrate between LANs with low-latency handoffs. Traditional approaches to mobility may be difficult to deploy and often lead to inefficient routing, but Software-Defined Networking (SDN) provides an intriguing alternative. This thesis identifies necessary requirements for a software-defined IP mobility system and then proposes one such system, the Software-Defined Mobile Campus Area Network (SD-MCAN) architecture. SD-MCAN employs an OpenFlow-based hybrid, label-switched routing scheme to efficiently route traffic flows between mobile hosts on the CAN. The proposed architecture is then implemented as an application on the existing POX controller and evaluated on virtual and hardware testbeds. Experimental results show that SD-MCAN can process handoffs with less than 90 ms latency, suggesting that the system can support data-intensive services on mobile host devices. Finally, the POX prototype is open-sourced to aid in future research