156 research outputs found
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
MOBILITY SUPPORT ARCHITECTURES FOR NEXT-GENERATION WIRELESS NETWORKS
With the convergence of the wireless networks and the Internet and the booming
demand for multimedia applications, the next-generation (beyond the third generation, or
B3G) wireless systems are expected to be all IP-based and provide real-time and non-real-time
mobile services anywhere and anytime. Powerful and efficient mobility support is
thus the key enabler to fulfil such an attractive vision by supporting various mobility
scenarios. This thesis contributes to this interesting while challenging topic.
After a literature review on mobility support architectures and protocols, the thesis
starts presenting our contributions with a generic multi-layer mobility support framework,
which provides a general approach to meet the challenges of handling comprehensive
mobility issues. The cross-layer design methodology is introduced to coordinate the
protocol layers for optimised system design. Particularly, a flexible and efficient cross-layer
signalling scheme is proposed for interlayer interactions. The proposed generic
framework is then narrowed down with several fundamental building blocks identified to
be focused on as follows.
As widely adopted, we assume that the IP-based access networks are organised into
administrative domains, which are inter-connected through a global IP-based wired core
network. For a mobile user who roams from one domain to another, macro (inter-domain)
mobility management should be in place for global location tracking and effective handoff
support for both real-time and non-real-lime applications. Mobile IP (MIP) and the Session
Initiation Protocol (SIP) are being adopted as the two dominant standard-based macro-mobility
architectures, each of which has mobility entities and messages in its own right.
The work explores the joint optimisations and interactions of MIP and SIP when utilising
the complementary power of both protocols. Two distinctive integrated MIP-SIP
architectures are designed and evaluated, compared with their hybrid alternatives and other
approaches. The overall analytical and simulation results shown significant performance
improvements in terms of cost-efficiency, among other metrics.
Subsequently, for the micro (intra-domain) mobility scenario where a mobile user
moves across IP subnets within a domain, a micro mobility management architecture is
needed to support fast handoffs and constrain signalling messaging loads incurred by intra-domain
movements within the domain. The Hierarchical MIPv6 (HMIPv6) and the Fast
Handovers for MIPv6 (FMIPv6) protocols are selected to fulfil the design requirements.
The work proposes enhancements to these protocols and combines them in an optimised
way. resulting in notably improved performances in contrast to a number of alternative
approaches
Resource Allocation in 4G and 5G Networks: A Review
The advent of 4G and 5G broadband wireless networks brings several challenges with respect to resource allocation in the networks. In an interconnected network of wireless devices, users, and devices, all compete for scarce resources which further emphasizes the fair and efficient allocation of those resources for the proper functioning of the networks. The purpose of this study is to discover the different factors that are involved in resource allocation in 4G and 5G networks. The methodology used was an empirical study using qualitative techniques by performing literature reviews on the state of art in 4G and 5G networks, analyze their respective architectures and resource allocation mechanisms, discover parameters, criteria and provide recommendations. It was observed that resource allocation is primarily done with radio resource in 4G and 5G networks, owing to their wireless nature, and resource allocation is measured in terms of delay, fairness, packet loss ratio, spectral efficiency, and throughput. Minimal consideration is given to other resources along the end-to-end 4G and 5G network architectures. This paper defines more types of resources, such as electrical energy, processor cycles and memory space, along end-to-end architectures, whose allocation processes need to be emphasized owing to the inclusion of software defined networking and network function virtualization in 5G network architectures. Thus, more criteria, such as electrical energy usage, processor cycle, and memory to evaluate resource allocation have been proposed. Finally, ten recommendations have been made to enhance resource allocation along the whole 5G network architecture
Contributions to Vehicular Communications Systems and Schemes
La derniÚre décennie a marqué une grande hausse des applications véhiculaires comme une nouvelle source de revenus et un facteur de distinction dans l'industrie des véhicules. Ces applications véhiculaires sont classées en deux groupes : les applications de sécurité et les
applications d'info divertissement. Le premier groupe inclue le changement intelligent de voie, l'avertissement de dangers de routes et la prévention coopérative de collision qui comprend la vidéo sur demande (VoD), la diffusion en direct, la diffusion de météo et de nouvelles et les jeux
interactifs. Cependant, Il est à noter que d'une part, les applications véhiculaires d'info divertissement nécessitent une bande passante élevée et une latence relativement faible ; D'autre part, les applications de sécurité requiÚrent exigent un délai de bout en bout trÚs bas et un canal de
communication fiable pour la livraison des messages d'urgence. Pour satisfaire le besoin en applications efficaces, les fabricants de véhicules ainsi que la
communautĂ© acadĂ©mique ont introduit plusieurs applications Ă lâintĂ©rieur de vĂ©hicule et entre vĂ©hicule et vĂ©hicule (V2V). Sauf que, l'infrastructure du rĂ©seau sans fil n'a pas Ă©tĂ© conçue pour gĂ©rer les applications de vĂ©hicules, en raison de la haute mobilitĂ© des vĂ©hicules, de l'imprĂ©visibilitĂ©
du comportement des conducteurs et des modÚles de trafic dynamiques. La relÚve est l'un des principaux défis des réseaux de véhicules, car la haute mobilité exige au
réseau sans fil de faire la relÚve en un trÚs court temps. De plus, l'imprévisibilité du comportement du conducteur cause l'échec des protocoles proactifs traditionnels de relÚve, car la prédiction du prochain routeur peut changer en fonction de la décision du conducteur. Aussi, le réseau de véhicules peut subir une mauvaise qualité de service dans les régions de relÚve en raison d'obstacles naturels, de véhicules de grande taille ou de mauvaises conditions météorologiques. Cette thÚse se concentre sur la relÚve dans l'environnement des véhicules et son effet sur les
applications vĂ©hiculaires. Nous proposons des solutions pratiques pour les rĂ©seaux actuellement dĂ©ployĂ©s, principalement les rĂ©seaux LTE, l'infrastructure vĂ©hicule Ă vĂ©hicule (V2V) ainsi que les outils efficaces dâĂ©mulateurs de relĂšves dans les rĂ©seaux vĂ©hiculaires.----------ABSTRACT: The last decade marked the rise of vehicular applications as a new source of revenue and a key differentiator in the vehicular industry. Vehicular Applications are classified into safety and infotainment applications. The former include smart lane change, road hazard warning, and
cooperative collision avoidance; however, the latter include Video on Demand (VoD), live streaming, weather and news broadcast, and interactive games. On one hand, infotainment
vehicular applications require high bandwidth and relatively low latency; on the other hand, safety applications requires a very low end to end delay and a reliable communication channel to deliver emergency messages. To satisfy the thirst for practical applications, vehicle manufacturers along with research institutes introduced several in-vehicle and Vehicle to Vehicle (V2V) applications. However, the wireless
network infrastructure was not designed to handle vehicular applications, due to the high mobility of vehicles, unpredictability of driversâ behavior, and dynamic traffic patterns. Handoff is one of the main challenges of vehicular networks since the high mobility puts pressure on the wireless network to finish the handoff within a short period. Moreover, the unpredictability of driver behavior causes the traditional proactive handoff protocols to fail, since the prediction of the next router may change based on the driverâs decision. Moreover, the vehicular network may
suffer from bad Quality of Service (QoS) in the regions of handoff due to natural obstacles, large vehicles, or weather conditions. This thesis focuses on the handoff on the vehicular environment and its effect on the vehicular
applications. We consider practical solutions for the currently deployed networks mainly Long Term Evolution (LTE) networks, the Vehicle to Vehicle (V2V) infrastructure, and the tools that can be used effectively to emulate handoff on the vehicular networks
HUC-HISF: A Hybrid Intelligent Security Framework for Human-centric Ubiquitous Computing
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Pro-collaborative mobile systems in next generation IP networks
Computing system designs of today take on either the interactive or the proactive
form. Motivated by the userâs desire to make his/her computing experience more
intelligent and personalised, the progression from interactive (human-centred) to
proactive (human-supervised) is evident. It can be observed that current research
mainly emphasises the user as the dominant focus of a user-system interaction.
Consider a model that we called the opponent-process model. It contains two
processes, one representing the user and the other the system, where both processes
are capable of dominating each other, though working collaboratively towards a
predefined task. We argue the necessity to design computing systems which are
balanced in this model, such that the system process, at times, becomes the dominant
process. We refer to this as the pro-collaborative design form.
We dissect mobility into the notion of a nomadic user and the notion of a
nomadic system. The examination into the nomadic user problem space reveals the
potential for applying the pro-collaborative approach in optimising handoff
management. Significant performance advantages can be obtained with our proposed
S-MIP framework, based on the pro-collaborative design, when compared with
established handoff latency optimisation schemes. The key differentiator lies in its
indicative approach in addressing handoff ambiguity. Instead of passively
anticipating through prediction as to when a mobile user might cross network
boundaries (user-dominant), the system actively indicates to the user when, where
and how to handoff (system-dominant). This eliminates the handoff ambiguity.
Regarding the notion of a nomadic system, that is, the ability to move services
offered by computing systems to arbitrary points in the Internet, we explore the idea
of the dynamic extension of network services to a mobile user on-demand. Based on
the pro-collaborative form, we develop the METAMORPHOSE architecture which
facilitates such a dynamic service extension. By assuming the proliferation of
programmable network switches and computational resources within the Internet, we
re-examine how âlooseâ service agreements between network services providers can
be, to achieve such borderless moving-service offerings.
The viability of the pro-collaborative form is reflected through our design and
implementation of protocols and architectures which address the notion of nomadic
user and nomadic system
MROM scheme to improve handoff performance in mobile networks
Mobile Router (MR) mobility supported by Network Mobility
Basic Support Protocol (NEMO BS) is a Mobile IPv6 (MIPv6) extension that
supports Host Mobility. Proposed Multihoming and Route Optimization for
MANEMO (MROM) scheme is designed to provide Route Optimization (RO)
and Multihomed in NEMO architectures. This paper proposes two novel
schemes; MANEMO routing scheme and Multihoming-based scheme. These
are to provide support for next generation networks. The proposed MROM
scheme differs from other schemes for NEMO environment because it considers
the requirements of more application flows parameters as packet lost delivery,
handoff delay as well as throughput). Another difference is that not only the
network infrastructure can begin the functionality of flow routing, but also an
Edge Mobile Router (EMR) can do this flow for routing. Moreover, it utilizes
the state of the art and presently active access network to perform the separation
of each flow in mobile network. Thus, proposed MROM exhibits multihoming
features and improves handoff performance by initiating flow-based fast
registration process in NEMO environment. A handoff method is proposed with
enhanced functionalities of the Local Mobility Anchors (LMA), Mobile Routers
(MRs) and signaling messages with a view to achieve continuous connectivity
through handoff in NEMO. Both analytical and simulation approaches are used.
Analytical evaluation is carried out to analyze packet delivery lost and handoff
delay of our proposed scheme. It was also shown that cost of signaling
messages and packet delivery are contributing to total handoff cost. At the
simulation part, network simulator 3 (NS 3) has been used as the tool to get
performance metrics that have been considered like packet delivery ratio,
handoff delay, and packet loss. Our proposed scheme (MROM) has been
benchmarking to the standard NEMO BS Protocol and P-NEMO. In this paper,
we discuss proposed MROM for next generation networks, providing detailed
analysis with a numerical model, proposed MROM, by maximizing the handoff
performance, has been justified to have better mobility support than the
ordinary NEMO BS Protocol and PNEMO.
KeywordsâMROM, MANEMO, RO, Multihomed, Handoff
Recommended from our members
Game theory for dynamic spectrum sharing cognitive radio
This thesis was submitted for the degree of Doctor of Philosophy and was awarded by Brunel University on 21 June 2010.âGame Theoryâ is the formal study of conflict and cooperation. The theory is based on a set of tools that have been developed in order to assist with the modelling and analysis of individual, independent decision makers. These actions potentially affect any decisions, which are made by other competitors. Therefore, it is well suited and capable of addressing the various issues linked to wireless communications. This work presents a Green Game-Based Hybrid Vertical Handover Model. The model is used for heterogeneous wireless networks, which combines both dynamic (Received Signal Strength and Node Mobility) and static (Cost, Power Consumption and Bandwidth) factors. These factors control the handover decision process; whereby the mechanism successfully eliminates any unnecessary handovers, reduces delay and overall number of handovers to 50% less and 70% less dropped packets and saves 50% more energy in comparison to other mechanisms. A novel Game-Based Multi-Interface Fast-Handover MIPv6 protocol is introduced in this thesis as an extension to the Multi-Interface Fast-handover MIPv6 protocol. The protocol works when the mobile node has more than one wireless interface. The protocol controls the handover decision process by deciding whether a handover is necessary and helps the node to choose the right access point at the right time. In addition, the protocol switches the mobile nodes interfaces âONâ and âOFFâ when needed to control the mobile nodeâs energy consumption and eliminate power lost of adding another interface. The protocol successfully reduces the number of handovers to 70%, 90% less dropped packets, 40% more received packets and acknowledgments and 85% less end-to-end delay in comparison to other Protocols. Furthermore, the thesis adapts a novel combination of both game and auction theory in dynamic resource allocation and price-power-based routing in wireless Ad-Hoc networks. Under auction schemes, destinations nodes bid the information data to access to the data stored in the server node. The server will allocate the data to the winner who values it most. Once the data has been allocated to the winner, another mechanism for dynamic routing is adopted. The routing mechanism is based on the source-destination cooperation, power consumption and source-compensation to the intermediate nodes. The mechanism dramatically increases the sellerâs revenue to 50% more when compared to random allocation scheme and briefly evaluates the reliability of predefined route with respect to data prices, source and destination cooperation for different network settings. Last but not least, this thesis adjusts an adaptive competitive second-price pay-to-bid sealed auction game and a reputation-based game. This solves the fairness problems associated with spectrum sharing amongst one primary user and a large number of secondary users in a cognitive radio environment. The proposed games create a competition between the bidders and offers better revenue to the players in terms of fairness to more than 60% in certain scenarios. The proposed game could reach the maximum total profit for both primary and secondary users with better fairness; this is illustrated through numerical results
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