9 research outputs found
Performance analysis of a new mobility/QoS-aware architecture
Ideally, the future Internet must provide acceptable Quality of Service (QoS) to mobile users that are running real-time applications and are moving across different access points at high speeds. The user mobility presents a great challenge to the network layer in order to maintain users on going connections. Currently, the Internet protocol that manages the user mobility at the network level is the Mobile Internet Protocol (MIP). This protocol, when a mobile user changes its point of attachment, maintains the same IP address for mobile node, so that user mobility became invisible to the application level and thus avoiding a connection interruption. Although, MIP standard allows the user mobility while maintaining an uninterrupted connection to an application, it does not have any concerns with the QoS support provided to applications with more strict performance requirements such as real-time applications. This paper addresses the issue of mobility and QoS management principles as well as the mobility and QoS management integration in the sense of build a QoS-aware architecture for mobile Internet. After covering the mobility and QoS management principles and integration, this paper also proposes a new QoS-aware architecture for mobile Internet. This new architecture takes into account the specific characteristics of mobile networks in order to design an integrated Mobility/QoS-aware management architecture suitable for real-time applications requirements. The simulation results indicate that the suggested architecture is able to provide acceptable QoS levels to real-time applications that are running in mobiles devices.(undefined
A QoS-enable solution for mobile environments
This paper addresses the problem of designing a suitable Quality of Service (QoS) solution for mobile environments. The proposed solution deploys a dynamic QoS provisioning scheme able to deal with service protection during node mobility within a local domain, presenting extensions to deal with global mobility. The dynamic QoS provisioning encompasses a QoS architecture that uses explicit and implicit setup mechanisms to request resources from the network for the purpose of supporting control plane functions and optimizing resource allocation.
Abstract--- For efficient resource allocation, the resource and mobility management schemes have been coupled resulting in a QoS/Mobility aware network architecture able to react proactively to mobility events. Both management schemes have been optimized to work together, in order to support seamless handovers for mobile users running real-time applications.
Abstract--- The analysis of performance improvement and the model parametrization of the proposed solution have been evaluated using simulation. Simulation results show that the solution avoids network congestion and also the starvation of less priority DiffServ classes. Moreover, the results also show that bandwidth utilization for priority classes is levered and that the QoS offered to Mobile Node's (MN's) applications, within each DiffServ class, is maintained in spite of MN mobility.
Abstract--- The proposed model is simple, easy to implement and takes into account the mobile Internet requirements. Simulation results show that this new methodology is effective and able to provide QoS services adapted to application requests
A micro-mobility solution for supporting QoS in global mobility
Today, users want to have simultaneously mobility, Quality of Service (QoS) and be always connected to Internet. Therefore, this paper proposes a QoS micro-mobility solution able to provide QoS support for global mobility. The solution comprises enhancements in the mobility management of Mobile IPv6 (MIPv6) and in the resources management of Differentiated Services (DiffServ) QoS model. The mobility management of MIPv6 was extended with fast and local handovers to improve its efficiency in micro-mobility scenarios with frequent handovers. The DiffServ resource management has been extended with adaptive and dynamic QoS provisioning to improve resources utilization in mobile IP networks. Further, in order to improve resources utilization the mobility and QoS messages were coupled, providing a resource management able to, proactively, react to mobile events. The performance improvement of the proposed solution and the model parametrization was evaluated using a simulation model. Simulation results indicate that the solution avoids network congestion and starvation of less priority DiffServ classes. Moreover, the results also indicate that bandwidth utilization for priority classes increases and the QoS offered to MN's applications, in each DiffServ class, keeps up unchangeable with MN mobility.(undefined
A QoS-enabled resource management scheme for F-HMIPv6 micro mobility approach
In the near future, wireless networks will certainly run real-time applications with special Quality of Service (QoS) requirements. In this context micro mobility management schemes such as Fast Handovers over Hierarchical Mobile IPv6 (F-HMIPv6) will be a useful tool in reducing Mobile IPv6 (MIPv6) handover disruption and thereby to improve delay and losses. However, F-HMIPv6 alone does not support QoS requirements for real-time applications. Therefore, in order to accomplish this goal, a novel resource management scheme for the Differentiated Services (DiffServ) QoS model is proposed to be used as an add-on to F-HMIPv6. The new resource management scheme combines the F-HMIPv6 functionalities with the DiffServ QoS model and with network congestion control and dynamic reallocation mechanisms in order to accommodate different QoS traffic requirements. This new scheme based on a Measurement-Based Admission Control (MBAC) algorithm is effective, simple, scalable and avoids the well known traditional resource reservation issues such as state maintenance, signaling overhead and processing load. By means of the admission evaluation of new flows and handover flows, it is able to provide the desired QoS requirements for new flows while preserving the QoS of existing ones. The evaluated results show that all QoS metrics analyzed were significantly improved with the new architecture indicating that it is able to provide a highly predictive QoS support to F-HMIPv6
QoS-aware Mobility Management in IP-based Communication Networks
Der allgegenwärtige Zugang zu Informationen, jederzeit und überall, ist ein
wichtiges Merkmal künftiger All-IP-Mobilfunktnetze, die verschiedene
Systeme miteinander verbinden, dabei dynamischer und flexibler sein
werden. Der Einsatz dieser Netze erfordert es jedoch, viele
Herausforderungen zu überwinden. Eine der wichtigsten im Rahmen dieser
Arbeit, ist die Frage, wie Quality of Service (QoS) Eigenschaften in
solchen hoch dynamischen, mobilen Umgebungen zu garantieren sind. Bekanntermaßen beeinflusst die Mobilität von Mobilknoten (MN) die Dienstgüte in mobilen Netzen, da QoS-Parameters für
die Ende-zu-Ende-Kommunikation vereinbart werden. Daher müssen Lösungen
entwickelt werden, die nahtlose Mobilität, bei gleichzeitigen QoS-Garantien
nach Handoffs, unterstützen. Diese Herausforderung ist das Hauptziel der
vorliegenden Dissertation, die einen umfassenden Überblick über die
bestehenden Mobilitäts- und QoS-Managment-Lösungen in IP-basierten Netzen
liefert, gefolgt von einem Einblick in Methoden zur Kopplung von
Mobilitätsmanagement und QoS-Lösungen. Nach Betrachtung der Vor- und
Nachteile bestehender Ansätze, kommt die Dissertation zu dem Schluss, dass
hybride Strategien vielversprechend sind und zu praktikablen Lösungen
weiterentwickelt werden können, die sowohl Mobilitäts- als auch
QoS-Anforderungen auf effiziente Weise,in allen zukünftigen IP-Mobilfunknetzen erfüllen können. Auf dieser Grundlage schlägt die Dissertation ein neues Hybrid-Protokoll, genannt
"QoS-aware Mobile IP Fast Authentication Protocol" (QoMIFA), vor. Unser
Vorschlag integriert MIFA als Mobilitäts-Management-Protokoll mit RSVP als
QoS Reservierungsprotokoll. MI-FA wird aufgrund seiner Fähigkeit zu
schnellen, sicheren und robusten Handoffs gewählt. RSVP hingegen dient als
Standardlösung zur Bereitstellung von QoS in bestehenden IP-basierten
Netzen. Unter Einhaltung der Hybrid-Architektur wird RSVP um ein neues
Objekt, genannt "Mobility Object" erweitert, welches
MIFA-Kontrollnachrichten kapselt. Nach der Spezifikation des neuen
Vorschlags, bewertet die Dissertation auch seine Leistung im Vergleich zu
dem bekannten "Simple QoS Signaling Protocol" (Simple QoS), mittels
Simulationsstudien, modelliert mit dem "Network Simluator 2" (NS2). In der
Auswertung werden der Einflusses der Netzwerklast und der Geschwindigkeit
des Mobilknotens untersucht. Die hierzu verwendeten Leistungsparameter
umfassen die Ressourcen-Reservierungs-Latenz, die Anzahl verlorener Pakete
pro Handoff, die Anzahl der, vor Abschluss der Reservierung, mit
Best-Effort-Eigenschaften übertragenen Pakete pro Handoff und die
Wahrscheinlichkeit von Verbindungsabbrüchen. Unsere mittels Simulation
erzielten Ergebnisse zeigen, dass QoMIFA schnelle und nahtlose Handoffs mit
schneller Ressourcenreservierung nach Handoffs kombinieren kann. Unter
Berücksichtigung des Einflusses der Netzwerklast, ist nachweisbar, dass
QoMIFA eine besser Leistung als Simple QoS in allen untersuchten Szenarien
mit geringer, mittlerer und hoher Last erreicht. Bei Betrachtung des
Einflusses der Bewegungsgeschwindigkeit des Mobilknotens auf die Leistung,
lassen sich unter beiden Protokollen Ping-Pong-Effekte beobachten, welche
zu höheren Ressourcen-Reservierungs-Latenzen, mehr verlorenen Paketen und
mehr Best-Effort-Paketen pro Handoff bei geringeren Geschwindigkeiten
führen. Der stärkste Einfluss dieser Pinp-Pong-Effekte ist jeweils bei 3
km/h zu beobachten. Allerdings verhält sich QoMIFA unter allen untersuchten
Bewegungsgeschwindigkeiten besser als Simple QoS und kann Mobilknoten auch
bei hohen Geschwindigkeiten bedienen. In Anschluss an die
simulationsgestützte Evaluierung, schätzt die Dissertation die
Signalisierungskosten beider Protokolle unter Betrachtung der Kosten für
Ortslokalise-rung und Paketzustellung. Im Ergebnis erreicht QoMIFA die
zuvor genannten Leistungsverbesserungen auf Kosten von größeren
Ortslokalisierungskosten und leicht höherer Paketzustellungskosten.Ubiquitous access to information anywhere, anytime and anyhow is an
important feature of future all-IP mobile communication networks, which
will interconnect various systems and be more dynamic and flexible. The
deployment of these networks, however, requires overcoming many challenges.
One of the main challenges of interest for this work is how to provide
Qual-ity of Service (QoS) guarantees in such highly dynamic mobile
environments.As known, mobility of Mobile Nodes (MNs) affects the QoS in
mobile networks since QoS parameters are made for end-to-end
communications. Therefore, it is a challenge to develop new solutions
capable of supporting seamless mobility while simultaneously providing QoS
guarantees after handoffs. Addressing this challenge is the main objective
of this dissertation, which provides a comprehensive overview of mobility
management solutions and QoS mech-anisms in IP-based networks followed by
an insight into how mobility management and QoS solutions can be coupled
with each other. Following the highlight of the state of art along with the
pros and cons of existing approaches, the dissertation concludes that
hybrid strategies are promising and can be further developed to achieve
solutions that are capable of simultaneous-ly supporting mobility and QoS,
simple from the implementation point of view, efficient and applicable to
future all-IP mobile communication networks.Based on this, the dissertation
proposes a new hybrid proposal named QoS-aware Mobile IP Fast
Authentication Protocol (QoMIFA). Our proposal integrates MIFA as a
mobility man-agement protocol with RSVP as a QoS reservation protocol. MIFA
is selected due to its capa-bility of the provision of fast, secure and
robust handoffs, while RSVP is chosen because it presents the standard
solution used to support QoS in existing IP-based networks. The hybrid
architecture is retained by introducing a new object, called “mobility
object”, to RSVP in or-der to encapsulate MIFA control messages.Following
the specification of the new proposal, the dissertation also evaluates its
perfor-mance compared to the well-known Simple QoS signaling protocol
(Simple QoS) by means of simulation studies modeled using the Network
Simulator 2 (NS2). The evaluation compris-es the investigation of the
impact of network load and MN speed. The performance measures we are
interested in studying comprise the resource reservation latency, number of
dropped packets per handoff, number of packets sent as best-effort per
handoff until the reservation is accomplished and probability of dropping
sessions. Our simulation results show that QoMIFA is capable of achieving
fast and smooth handoffs in addition to its capability of quickly
re-serving resources after handoffs. Considering the impact of network
load, QoMIFA outper-forms Simple QoS in all studied scenarios (low- ,
middle- and high-loaded scenarios). With respect to the impact of MN speed,
it can be observed that the impact of ping-pong effects is seen with both
protocols and results in higher resource reservation latency, more dropped
packets per handoff and more best-effort packets per handoff at low speeds
than at higher ones. The worst impact of ping-pong effects is seen at a
speed of 3 km/h when employing QoMIFA and Simple QoS, respectively.
However, QoMIFA remains performing significantly better than Simple QoS
under all studied MN speeds and can even properly serve MNs mov-ing at high
speeds.Following the simulative evaluation, the dissertation estimates the
signaling cost of both stud-ied protocols with respect to the location
update and packet delivery cost. Our results show that QoMIFA achieves the
above mentioned performance improvements at the cost of greater location
update cost and slightly higher packet delivery cost than Simple QoS
A QoS-aware architecture for mobile internet
Tese de doutoramento InformáticaHoje em dia, as pessoas pretendem ter simultaneamente mobilidade, qualidade de serviço e
estar sempre connectados à Internet. No intuito, de satisfazer estes clientes muito exigentes,
os mercados das telecomunicações estão a impor novos e dificeis desafios às redes móveis,
através da demanda, de heterogeneidade em termos de tecnologias de acesso rádio, novos
serviços, niveis de qualidade de serviço adequados aos requisitos das aplicações de tempo
real, elevada taxa de utilização do recursos disponiveis e melhor capacidade de desempenho.
A Internet foi concebida para fornecer serviços sem qualquer tipo de garantias de qualidade
às aplicações, apenas se comprometendo em oferecer o melhor serviço possível. No
entanto, nos útlimos anos diversos esforços foram levados a cabo no sentido de dotar a
Internet com o suporte à qualidade de serviço. Dos esforços desenvolvidos resultaram
dois paradigmas para o suporte da qualidade de serviço: o modelo de Serviços Integrados
(Integrated Services - IntServ) e o modelo de Serviços Diferenciados (Differentiated Services
- DiffServ). Todavia, estes modelos de qualidade de serviço (QoS) foram concebido antes
da existência da Internet móvel, portanto o desenvolvimento destes modelos não teve em
consideração a questão da mobilidade.
Por outro lado, o protocolo padrão actual para a Internet móvel, o MIPv6, revela algumas
limitações nos cenários onde os utilizadores estão constantemente a moverem-se para
outros pontos de acesso. Neste tipo de cenários, o MIPv6 introduz tempos de latência que
não são sustentáveis para aplicações com requisitos de QoS mais restritos. Os factos revelados,
demonstram que existe uma emergente necessidade de adaptar o actual protocolo de
mobilidade, e também de adaptar os modelos de QoS, ou então criar modelos alternativos
de QoS, para satisfazer às exigências do utilizador de hoje de redes móveis.
Para alcançar este objectivo o presente trabalho propõe melhorias no sistema de gestão
da mobilidade do protocolo MIPv6 e na gestão de recursos do modelo DiffServ. O MIPv6 foi
melhorado para os cenários de micro-mobilidade com a abordagem para micro-mobilidade do F-HMIPv6. Enquanto que, o modelo DiffServ foi melhorado para os ambientes móveis
com funcionalidades dinâmicas e adaptativas através da utilização de sinalização de QoS e
da gestão distribuida dos recursos.
A gestão da mobilidade e dos recursos foi também acoplada na solução proposta com o
propósito de optimizar a utilização dos recursos num meio onde os recursos são tipicamente
escassos.
O modelo proposto é simples, é de fácil implementação, tem em consideração os requisitos
da Internet móvel, e provou ser eficiente e capaz de fornecer serviços com QoS de
elevada fiabilidade às aplicações.Over the last few years, several network communication challenges have arisen as a
result of the growing number of users demanding Quality of Service (QoS) and mobility
simultaneously.
In order to satisfy these very demanding customers, the markets are imposing new
challenges to wireless networks by demanding heterogeneity in terms of wireless access
technologies, new services, suited QoS levels to real-time applications, high usability and
improved performance.
However, the Internet has been designed for providing application services without quality
guarantees. That explains why, in the last years several efforts have been made to
endow Internet with QoS support. From the developed efforts have resulted two QoS
paradigms: Integrated Services (IntServ) which offers the guaranteed service model and
the Differentiated Services (DiffServ) which offers the predictive service model.
Although these QoS models have been designed before the existence of mobile Internet,
so they do not consider the mobility issue. For instance, the guaranteed service model
requires that whenever a Mobile Node (MN) wants to move to a new location, the allocated
resources in the old path must be released and a new resource reservation in a new path must
be made, resulting in extra signaling overhead, heavy processing and state load. Therefore,
if handovers are frequent, large mobility and QoS signaling messages will be created in
the access networks. Consequently, significant scalability problems may arise with this type of
service model.
The predicted service model, on the other hand, requires an additional features such
as dynamic and adaptive resource management in order to be efficient in a very dynamic
network such as a mobile network.
A QoS solution for mobile environments must provide the capacity to adapt its resource
utilization to a changeable nature of wireless networks because they have a more dynamic behavior due to incoming or outgoing handovers. For this reason, a QoS signalization for
dynamic resource provisioning is necessary in order to supply adequate QoS levels to mobile
users.
On the other hand, the current standard protocol for mobile Internet, Mobile IPv6
(MIPv6), reveals limitations in scenarios where users are constantly moving to another
point of attachment. In these situations, MIPv6 introduces latency times that are not
sustainable for applications with strict QoS requirements.
All things considered, reveal the emerging need to adapt the current standard mobility
protocol and QoS models to satisfy today’s mobile user’s requirements.
To accomplish this goal, the present work proposes enhancements in terms of the MIPv6
protocol mobility management scheme as well as in DiffServ QoS model resource management.
The former was enhanced for micro-mobility scenarios with a specific combination of
FMIPv6 (Fast Mobile IPv6) and HMIPv6 (Hierarchical Mobile IPv6) protocols. Whereas,
the latter was enhanced for mobile environments with dynamic and adaptive features by
using QoS signalization as well as distributed resource management.
The mobility and resource management has also been coupled in the proposed solution
with the objective of optimizing the resource utilization in a environment where resources
are typically scarce.
In order to assess model performance as well as its parametrization, a simulation model
has been designed and implemented in the Network Simulator version two (NS-2).
The model´s performance evaluation has been conducted based on the respective data
acquired from statistical analysis in order to validate and consolidate the conclusions. Simulation
results indicate that the solution avoids network congestion and starvation of less
priority DiffServ classes.
Moreover, the results also indicate that bandwidth utilization for priority classes increases
and the QoS offered to MN’s applications, in each DiffServ class, remains unchangeable
with MN mobility.
The proposed model is simple and easy to implement. It considers mobile Internet
requirements and has proven to be effective and capable of providing services with highly
reliable QoS to mobile applications.Fundação para a Ciência e a Tecnologia (FCT) - Bolsa SFRH/BD/35245/200
Advanced Signaling Support for IP-based Networks
This work develops a set of advanced signaling concepts for IP-based networks. It proposes a design for secure and authentic signaling and provides QoS signaling support for mobile users. Furthermore, this work develops methods which allow for scalable QoS signaling by realizing QoS-based group communication mechanisms and through aggregation of resource reservations
Actas da 10ª Conferência sobre Redes de Computadores
Universidade do MinhoCCTCCentro AlgoritmiCisco SystemsIEEE Portugal Sectio