10 research outputs found
A Survey on Proxy Mobile IPv6 Handover
[EN] As wireless technologies have been improving in recent years, a mobility management mechanism is required to provide seamless and ubiquitous mobility for end users who are roaming among points of attachment in wireless networks. Thus, Mobile IPv6 was developed by the Internet Engineering Task Force (IETF) to support the mobility service. However, Mobile IPv6 is unable to fulfill the requirements of real-time applications, such as video streaming service and voice over IP service, due to its high handover (HO) latency. To address this problem, Proxy Mobile IPv6 (PMIPv6) has been introduced by the IETF. In PMIPv6, which is a network-based approach, the serving network controls mobility management on behalf of the mobile node (MN). Thus, the MN is not required to participate in any mobility-related signaling. However, the PMIPv6 still suffers from lengthy HO latency and packet loss during a HO. This paper explores an elaborated survey on the HO procedure of PMIPv6 protocols and proposed approaches accompanied by a discussion about their points of weakness.This work was supported in part by the University of Malaya under UMRG Grant (RG080/11ICT).Modares, H.; Moravejosharieh, A.; Lloret, J.; Salleh, R. (2016). A Survey on Proxy Mobile IPv6 Handover. IEEE Systems Journal. 10(1):208-217. https://doi.org/10.1109/JSYST.2013.2297705S20821710
Contributions to Vehicular Communications Systems and Schemes
La dernière 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 requièrent exigent un délai de bout en bout très 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
communauté académique ont introduit plusieurs applications à l’intérieur de véhicule et entre véhicule et véhicule (V2V). Sauf que, l'infrastructure du réseau sans fil n'a pas été conçue pour gérer les applications de véhicules, en raison de la haute mobilité des véhicules, de l'imprévisibilité
du comportement des conducteurs et des modèles de trafic dynamiques. La relève est l'un des principaux défis des réseaux de véhicules, car la haute mobilité exige au
réseau sans fil de faire la relève en un très court temps. De plus, l'imprévisibilité du comportement du conducteur cause l'échec des protocoles proactifs traditionnels de relève, 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 relève en raison d'obstacles naturels, de véhicules de grande taille ou de mauvaises conditions météorologiques. Cette thèse se concentre sur la relève dans l'environnement des véhicules et son effet sur les
applications véhiculaires. Nous proposons des solutions pratiques pour les réseaux actuellement déployés, principalement les réseaux LTE, l'infrastructure véhicule à véhicule (V2V) ainsi que les outils efficaces d’émulateurs de relèves dans les réseaux véhiculaires.----------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 drivers’ 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 driver’s 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
Improving initiation, decision and execution phases for vertical handover in heterogeneous wireless mobile networks
One of the challenging issues in Next Generation Wireless Systems (NGWS) is seamless Vertical Handover (VHO) during the mobility between different types of technologies (3GPP and non-3GPP) such as Global System for Mobile Communication (GSM), Wireless Fidelity (Wi-Fi), Worldwide Interoperability for Microwave Access (WiMAX), Universal Mobile Telecommunications System (UMTS) and Long Term Evolution (LTE). Therefore, the telecommunication operators are required to develop aninteroperability strategy for these different types of existing networks to get the best connection anywhere, anytime without interruption of the ongoing sessions. In order to identify this problem accurately, the research study presented in this thesis provides four surveys about VHO approaches found in the literature. In these surveys, we classify the existing VHO approaches into categories based on the available VHO techniques for which we present their objectives and performances issues. After that, we propose an optimised VHO approach based on the VHO approaches that have been studied in the literature and take into consideration the research problems and conclusions which arearisen in our surveys. The proposed approach demonstrates better performance (packet loss, latency and signaling cost), less VHO connection failure (probability of minimising VHO reject sessions), less complexity and an enhanced VHO compared with that foundin the literature. It consists of a procedure which is implemented by an algorithm. The proposed procedure of loose coupling and Mobile Internet Protocol version 4 (MIPv4) provides early buffering for new data packets to minimise VHO packet loss and latency. Analysis and simulation of the proposed procedure show that the VHO packet loss and latency are significantly reduced compared with previous MIPv6 procedures found in the literature.The proposed algorithm is composed of two main parts: Handover Initiation and Optimum Radio Access Technologies (RATs) list of priority. The first part includes two main types of VHO and gives priority to imperative sessions over alternative sessions. IIIThis part is also responsible for deciding when and where to perform the handover by choosing the best RATs from the multiple ones available. Then, it passes them to the decision phase. This results in reducing the signaling cost and the inevitable degradation in Quality of Service (QoS) as a result of avoiding unnecessary handover processes. The second part defines RATs list of priority to minimise VHO connection failure. Analysis and simulation based performance evaluations then demonstrate that the proposed algorithm outperforms the traditional algorithms in terms of: (a) the probability of VHOconnection failure as a result of using the optimum RATs list of priority and (b) thesignaling cost and the inevitable degradation in QoS as a result of avoiding unnecessary handover processes
Estudio de la movilidad en redes de siguiente generación
El continuo avance de las redes de telecomunicaciones nos proporciona cada
vez más facilidades en todos los ámbitos de nuestra vida. En este caso, nos hemos
centrado en el estudio de la movilidad en Redes de Siguiente Generación.
Una parte del presente proyecto se ha realizado en colaboración con Deutsche
Telekom AG, durante una estancia de seis meses trabajando como colaboradora en
sus laboratorios con emplazamiento en Berlín.
El principal objetivo de este proyecto ha sido realizar un estudio sobre los
diferentes estándares y tecnologías que facilitan la movilidad en Redes de
Siguiente Generación. Por ello, en la primera parte se han estudiado los diferentes
grupos de trabajo centrados en este aspecto, así como se ha recabado información
sobre productos y soluciones disponibles en el mercado, para obtener una visión
global de la situación actual.
Como se puede comprobar más adelante, esta primera parte es la más extensa
de todo el documento. Esto se debe a que es, probablemente, la parte más
importante del trabajo, ya que contiene el estudio de los mecanismos que más tarde
nos servirán para dar una solución teórica a los distintos escenarios que se
plantean.
En la segunda parte del proyecto, nos hemos centrado en desarrollar varios
escenarios de interés en sistemas de Redes de Siguiente Generación y aportar, de
forma posterior, posibles soluciones teóricas.
Para finalizar, se han expuesto las conclusiones extraídas como resultado del
trabajo y los aspectos que se podrán tratar sobre el mismo en un futuro próximo.Ingeniería de Telecomunicació
Distribuição de vídeo para grupos de utilizadores em redes móveis heterogéneas19
The evolutions veri ed in mobile devices capabilities (storage capacity, screen
resolution, processor, etc.) over the last years led to a signi cant change
in mobile user behavior, with the consumption and creation of multimedia
content becoming more common, in particular video tra c. Consequently,
mobile operator networks, despite being the target of architectural evolutions
and improvements over several parameters (such as capacity, transmission
and reception performance, amongst others), also increasingly become more
frequently challenged by performance aspects associated to the nature of
video tra c, whether by the demanding requirements associated to that
service, or by its volume increase in such networks.
This Thesis proposes modi cations to the mobile architecture towards a more
e cient video broadcasting, de ning and developing mechanisms applicable
to the network, or to the mobile terminal. Particularly, heterogeneous
networks multicast IP mobility supported scenarios are focused, emphasizing
their application over di erent access technologies. The suggested changes
are applicable to mobile or static user scenarios, whether it performs the role
of receiver or source of the video tra c. Similarly, the de ned mechanisms
propose solutions targeting operators with di erent video broadcasting goals,
or whose networks have di erent characteristics. The pursued methodology
combined an experimental evaluation executed over physical testbeds,
with the mathematical evaluation using network simulation, allowing the
veri cation of its impact on the optimization of video reception in mobile
terminalsA evolução veri cada nas características dos dispositivos moveis (capacidade
de armazenamento, resolução do ecrã, processador, etc.) durante os
últimos anos levou a uma alteração signi cativa nos comportamentos dos
utilizadores, sendo agora comum o consumo e produção de conteúdos
multimédia envolvendo terminais móveis, em particular o tráfego vídeo.
Consequentemente, as redes de operador móvel, embora tendo também sido
alvo constante de evoluções arquitecturais e melhorias em vários parâmetros
(tais como capacidade, ritmo de transmissão/recepção, entre outros), vêemse
cada vez mais frequentemente desa adas por aspectos de desempenho
associados à natureza do tráfego de vídeo, seja pela exigência de requisitos
associados a esse serviço, quer pelo aumento do volume do mesmo nesse
tipo de redes.
Esta Tese propôe alterações à arquitetura móvel para a disseminação de vídeo
mais e ciente, de nindo e desenvolvendo mecanismos aplicáveis à rede, ou
ao utilizador móvel. Em particular, são focados cenários suportados por IP
multicast em redes móveis heterogéneas, isto é, com ênfase na aplicação
destes mecanismos sobre diferentes tecnologias de acesso. As alterações
sugeridas aplicam-se a cenários de utilizador estático ou móvel, sendo este a
fonte ou receptor do tráfego vídeo. Da mesma forma, são propostas soluções
tendo em vista operadores com diferentes objectivos de disseminação de
vídeo, ou cujas redes têm diferentes características. A metodologia utilizada
combinou a avaliação experimental em testbeds físicas com a avaliação
matemática em simulações de redes, e permitiu veri car o impacto sobre
a optimização da recepção de vídeo em terminais móveisPrograma Doutoral em Telecomunicaçõe
Arquitectura de red de acceso móvil de cuarta generación : mobile-IP RAN
Esta tesis aborda el problema de las arquitecturas de acceso radio, en el ámbito de las redes móviles de cuarta generación definidas en entornos de movilidad IP. Uno de los principales beneficios del uso estas propuestas es la simplificación de la red móvil, haciéndola menos dependiente de la tecnología de acceso radio, y por ende permitiendo el uso de una red troncal común a las diferentes tecnologías radio existentes. En estas redes, la movilidad del terminal, la infraestructura de red y la seguridad son los aspectos más importantes que se han tomado en consideración en su diseño. A pesar de los avances en la investigación y estandarización de los mecanismos de movilidad basados en IP, existen aún limitaciones en la funcionalidad ofrecida por las redes de acceso radio propuestas. Estas limitaciones se refieren a servicios de la red de acceso radio, que no son específicos al nivel de red (IP), pero que deben ofrecerse por la red para el correcto funcionamiento de los servicios generales de la red móvil, e incluyen los servicios de gestión de los recursos radio, movilidad (handover), sincronización de usuario y red, descubrimiento de servicios y cálculo de la posición del móvil. El objetivo principal de esta tesis es la definición de una red de acceso radio basada en IP móvil que integre las principales funciones de las redes de acceso móvil de tercera generación y aquellas consideradas de cuarta generación. Esta nueva arquitectura permite compartir la infraestructura de acceso radio entre las distintas tecnologías radio existentes, simplificando la red y los costos asociados. Asimismo, los proveedores de servicios móviles podrán incorporar de forma integrada nuevas tecnologías radio, sin necesidad de añadir más infraestructura que la equivalente a las estaciones base. Las aportaciones principales de esta tesis, dentro del objetivo general, se pueden resumir de la siguiente manera. En primer lugar, se definen los requisitos que debe cumplir la red de acceso móvil de cuarta generación, en cuanto a los servicios de red y usuario proporcionados. La segunda aportación, y considerada la aportación principal, es la definición de una arquitectura de red de acceso basada en IPv6 móvil, denominada Mobile-IP RAN, que incluye la definición de los elementos de red que la componen, así como sus interfaces y protocolos, que permite ofrecer los servicios de acceso a la red, movilidad de usuario, transferencia de datos, sincronización y localización de usuarios. Como parte de la arquitectura, se define, a través de diagramas de secuencia de mensajes, el comportamiento dinámico de las principales funciones proporcionadas por la red de acceso propuesta. Por último, se lleva a cabo la evaluación de los modelos de movilidad, de determinación de la posición (como parte del servicio de localización de usuario) y de sincronización propuestos, analizando sus parámetros fundamentales que permitan optimizar el desempeño de estos modelos, así como su aplicabilidad en las distintas redes de acceso radio. ______________________________________________This thesis approaches the architecture of radio access networks in the context of fourth
generation mobile networks, these being defined in IP mobility environments. One of the main
benefits of these proposals is the simplification of the mobile network, now less dependent of the
radio access technologies, and allowing the use of a common core network for all existing radio
technologies. On these proposals, user mobility, network infrastructure and security are main
aspects considered on the design.
In spite of the advances on research and standardization of the IP-based mobility mechanisms,
there are still limitations in the features offered by the proposed radio access networks. These
limitations refers to radio access network service features, not specific to the (IP) network layer,
but necessary for the correct operation of the general network and user services, that includes
radio resource management, mobility (e.g. handover), network and user synchronization, service
discovery and user position calculation.
The main objective of this thesis is the definition of a radio access network architecture based on
Mobile IPv6 that integrates the main features of the third-generation mobile access networks and
those of the fourth generation. This architecture allows the use of the radio access infrastructure
among the different existing radio access technologies, simplifying the network and its associated
costs. Moreover, with this architecture, mobile service providers may incorporate new radio
technologies in a seamless way, without adding more infrastructure than the base stations.
The main contributions of this work can be summarized as follows. First, we define the
requirements of the fourth-generation radio access networks related to the network and user
services provided.
Second, and considered the main contribution of this thesis, is the definition of a Mobile-IPv6
based radio access network architecture, named Mobile-IP RAN, that includes the definition of its
network elements, as well as its network interfaces and protocols, that allow services including
network access, user mobility, user data transfer, synchronization and location services. As part
of the architecture, and through the use of Message Sequence Charts, we define the dynamic
behavior of the main features offered by the proposed access network.
Last, we perform the evaluation of the proposed mobility, position determination and
synchronization models, analyzing their main parameters as well as their applicability in different
radio access networks