132 research outputs found
Roaming Real-Time Applications - Mobility Services in IPv6 Networks
Emerging mobility standards within the next generation Internet Protocol,
IPv6, promise to continuously operate devices roaming between IP networks.
Associated with the paradigm of ubiquitous computing and communication, network
technology is on the spot to deliver voice and videoconferencing as a standard
internet solution. However, current roaming procedures are too slow, to remain
seamless for real-time applications. Multicast mobility still waits for a
convincing design. This paper investigates the temporal behaviour of mobile
IPv6 with dedicated focus on topological impacts. Extending the hierarchical
mobile IPv6 approach we suggest protocol improvements for a continuous
handover, which may serve bidirectional multicast communication, as well. Along
this line a multicast mobility concept is introduced as a service for clients
and sources, as they are of dedicated importance in multipoint conferencing
applications. The mechanisms introduced do not rely on assumptions of any
specific multicast routing protocol in use.Comment: 15 pages, 5 figure
Forwarding Based Data Parallel Handoff for Real-Time QoS in Mobile IPv6 Networks
Real time mobile applications with guaranteed quality of service (QoS) are expected to be popular due to drastic increase of mobile Internet users. Many Resource ReSerVation Protocol (RSVP) based handover schemes in MIPv4 were studied in the literature for those services. However, the buffering overhead is unavoidable for the latency to optimize the route in new path establishment. Even though the data forwarding based schemes minimize the data loss and provide faster handoff, there are still some overheads when forwarding them and limitation on MIPv4. In this paper we propose a novel handoff scheme in MIPv6 based on forwarding which balances route traffic and reduces the overhead. The comprehensive performance evaluation shows that the disruption time and the signaling overhead are significantly reduced up to about 62 % and 73 % respectively, in comparison with well-known previous schemes discussed in cite{Low, Real}. Furthermore, it is able to transmit data with the reduced latency and guarantee the fast and secure seamless services
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
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
Mobility management in IP-Based Networks
Mobile communication networks experience a tremendous development clearly
evident from the wide variety of new applications way beyond classical
phone services. The tremendous success of the Internet along with the
demand for always-on connectivity has triggered the development of All-IP
mobile communication networks. Deploying these networks requires, however,
overcoming many challenges. One of the main challenges is how to manage the
mobility between cells connecting through an IP core in a way that
satisfies real-time requirements. This challenge is the focus of this
dissertation. This dissertation delivers an in-depth analysis of the
mobility management issue in IP-based mobile communication networks. The
advantages and disadvantages of various concepts for mobility management in
different layers of the TCP/IP protocol stack are investigated. In
addition, a classification and brief description of well-known mobility
approaches for each layer are provided. The analysis concludes that network
layer mobility management solutions seem to be best suited to satisfy the
requirements of future All-IP networks. The dissertation, therefore,
provides a comprehensive review of network layer mobility management
protocols along with a discussion of their pros and cons. Analyses of
previous work in this area show that the proposed techniques attempt to
improve the performance by making constraints either on access networks
(e.g. requiring a hierarchical topology, introducing of intermediate nodes,
etc.) or mobile terminals (e.g. undertaking many measurements, location
tracking, etc.). Therefore, a new technique is required that completes
handoffs quickly without affecting the end-to-end performance of ongoing
applications. In addition, it should place restrictions neither on access
networks nor on mobiles. To meet these requirements, a new solution named
Mobile IP Fast Authentication protocol (MIFA) is proposed. MIFA provides
seamless mobility and advances the state of the art. It utilizes the fact
that mobiles movements are limited to a small set of neighboring subnets.
Thus, contacting these neighbors and providing them in advance with
sufficient data related to the mobiles enable them to fast re-authenticate
the mobiles after the handoff. The dissertation specifies the proposal for
both IPv4 and IPv6. The specification of MIFA considers including many
error recovery mechanisms to cover the most likely failures. Security
considerations are studied carefully as well. MIFA does not make any
restrictions on the network topology. It makes use of layer 2 information
to optimize the performance and works well even if such information is not
available.In order to analyze our new proposal in comparison to a wide
range of well-known mobility management protocols, this dissertation
proposes a generic mathematical model that supports the evaluation of
figures such as average handoff latency, average number of dropped packets,
location update cost and packet delivery cost. The generic model considers
dropped control messages and takes different network topologies and
mobility scenarios into account. This dissertation also validates the
generic mathematical model by comparing its results to simulation results
as well as results of real testbeds under the same assumptions. The
validation proves that the generic model delivers an accurate evaluation of
the performance in low-loaded networks. The accuracy of the model remains
acceptable even under high loads. The validation also shows that simulation
results lie in a range of 23 %, while results of real testbeds lie in a
range of 30 % of the generic model?s results. To simplify the analysis
using the generic mathematical model, 4 new tools are developed in the
scope of this work. They automate the parameterization of mobility
protocols, network topologies and mobility scenarios. This dissertation
also evaluates the new proposal in comparison to well-known approaches
(e.g. Mobile IP, Handoff-Aware Wireless Access Internet Infrastructure
(HAWAII), etc.) by means of the generic mathematical model as well as
simulation studies modeled in the Network Simulator 2. The evaluation shows
that MIFA is a very fast protocol. It outperforms all studied protocols
with respect to the handoff latency and number of dropped packets per
handoff. MIFA is suitable for low as well as high speeds. Moreover, there
is no significant impact of the network topology on its performance. A main
advantage of MIFA is its robustness against the dropping of control
messages. It remains able to achieve seamless handoffs even if a dropping
occurs. The performance improvement is achieved, however, at the cost of
introducing new control messages mainly to distribute data concerning
mobile terminals to neighbor subnets. This results in more location update
cost than that resulting from the other mobility management protocols
studied. Due to excluding any constraints on the network topology, MIFA
generates the same packet delivery cost as Mobile IP and less than other
protocols.An additional focus of this dissertation is the development of an
adaptive eLearning environment that personalizes eLearning contents
conveying the topics of this dissertation depending on users?
characteristics. The goal is to allow researchers to quickly become
involved in research on mobility management, while learners such as
students are able to gain information on the topics without excess detail.
Analyses of existing eLearning environments show a lack of adaptivity
support. Existing environments focus mainly on adapting either the
navigation or the presentation of contents depending on one or more
selected users? characteristics. There is no environment that supports both
simultaneously. In addition, many user characteristics are disregarded
during the adaptivity process. Thus, there is a need to develop a new
adaptive eLearning environment able to eliminate these drawbacks. This
dissertation, therefore, designs a new Metadata-driven Adaptive eLearning
Environment (MAeLE). MAeLE generates personalized eLearning courses along
with building an adequate navigation at run-time. Adaptivity depends mainly
on providing contents with their describing metadata, which are stored in a
separate database, thus enabling reusing of eLearning contents. The
relation between the metadata that describe contents and those describing
learners are defined accurately, which enables a dynamic building of
personalized courses at run-time. A prototype for MAeLE is provided in this
dissertation as well
Mobile IP: state of the art report
Due to roaming, a mobile device may change its network attachment each time it moves to a new link. This might cause a disruption for the Internet data packets that have to reach the mobile node. Mobile IP is a protocol, developed by the Mobile IP Internet Engineering Task Force (IETF) working group, that is able to inform the network about this change in network attachment such that the Internet data packets will be delivered in a seamless way to the new point of attachment. This document presents current developments and research activities in the Mobile IP area
Fast and seamless mobility management in IPV6-based next-generation wireless networks
Introduction -- Access router tunnelling protocol (ARTP) -- Proposed integrated architecture for next generation wireless networks -- Proposed seamless handoff schemes in next generation wireless networks -- Proposed fast mac layer handoff scheme for MIPV6/WLANs
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