972 research outputs found
Quality-Oriented Mobility Management for Multimedia Content Delivery to Mobile Users
The heterogeneous wireless networking environment determined by the latest developments in wireless access technologies promises a high level of communication resources for mobile
computational devices. Although the communication resources provided, especially referring to bandwidth, enable multimedia streaming to mobile users, maintaining a high user perceived quality is still a challenging task. The main factors which affect quality in multimedia streaming over wireless networks are mainly the error-prone nature of the wireless channels and the user mobility. These factors determine a high level of dynamics of wireless communication resources, namely variations in throughput and packet loss as well as network availability and delays in delivering the data packets. Under these conditions maintaining a high level of quality, as perceived by the user, requires a quality oriented mobility management scheme. Consequently we propose the Smooth Adaptive Soft-Handover Algorithm, a novel quality oriented handover management scheme which unlike other similar solutions, smoothly transfer the data traffic from one network to another using multiple simultaneous connections. To estimate the capacity of each connection the novel Quality of Multimedia Streaming (QMS) metric is proposed. The QMS metric aims at offering maximum flexibility and efficiency allowing the applications to fine tune the behavior of the handover algorithm. The current simulation-based performance evaluation clearly shows the better
performance of the proposed Smooth Adaptive Soft-Handover Algorithm as compared with other handover solutions. The evaluation was performed in various scenarios including
multiple mobile hosts performing handover simultaneously, wireless networks with variable overlapping areas, and various network congestion levels
Network-driven handover in 5G
Currently, usersâ expectations regarding technological performance are constantly increasing. An example of this is the growing consumption of multimedia content via the Internet. Multimedia applications with a variable number of users/requests have variable demand over time that may expose the limitation of the network channels. This may cause a problem of demand mobility generated by the service/application. Each generation of mobile networks has speciïŹc handover processes, which in the case of 4G can be controlled according to the applications requirements, with the possibility of multiconnectivity. This process was massiïŹed in 5G. The main contribution of this dissertation is the development and analysis of decision models for controlling the video streaming and user association to a BS in the network architecture. The scenario considered refers to a football stadium with multiple points of view â video streams â that each spectator can request to view on their cell phone or tablet. The developed simulator models the stadium scenario using a combination of services, which occur on the 5G network. Vertical handover generated by the network is used,aidedbynetworkslicing. Thenetworkslicingactsinthepartofthebandwidthdivision between the diïŹerent antennas and allows the throughput of the diïŹerent broadcast (FeMBMS)channelsto becontrolledbytheservice -theradionetworkcapacitylimitsthe throughput. The results obtained in a case of 80000 spectators who select diïŹerent beams over time, considering8basestations(BS),showthatthequalityofexperienceishighonlywhenthe handover and the control of beam diïŹusion by BS are managed according to the application requirements. The network recovers from huge peaks by handling as many requests at once as possible. Instead of the user only getting the steam in a good quality or not getting it at all, the network performs a best-eïŹort solution of downgrading the quality of multicasting in order to expend less resources with the same quantity of requests. The network state is taken into consideration. Although there are load peaks on the network, it is never congested.Atualmente, as expectativas dos utilizadores em relação Ă capacidade tecnolĂłgica nĂŁo param de aumentar. Exemplo disso Ă© o crescente consumo de conteĂșdo multimĂ©dia atravĂ©s da Internet. AplicaçÔes multimĂ©dia com nĂșmero variĂĄvel de utilizadores e pedidos tĂȘm um ïŹuxo de serviço variĂĄvel ao longo do tempo. Esta variĂąncia pode expor a limitação de canais de rede, que consequentemente pode causar um problema de mobilidade gerado pelo serviço/aplicação. Cada geração de redes mĂłveis possui processos de handover de utilizadores especĂïŹcos, que no caso da geração 4G passou a ser controlado em função das aplicaçÔes, com a possibilidade de multiconectividade. Este processo foi massiïŹcado no 5G. A principal contribuição desta dissertação Ă© o desenvolvimento e anĂĄlise de modelos de decisĂŁo para controlar a difusĂŁo de vĂdeo e a associação de utilizadores Ă rede rĂĄdio na arquitetura da rede. O cenĂĄrio considerado reïŹete um estĂĄdio de futebol com vĂĄrios pontos de vista - diferentes feixes de vĂdeo - que cada espectador pode solicitar e visualizar no seu telemĂłvel ou tablet. O simulador desenvolvido modela o cenĂĄrio do estĂĄdio usando uma combinação de serviços, que ocorrem na rede 5G. Ă usado handover vertical gerado pela rede auxiliado por network slicing que atua na parte da divisĂŁo da largura de banda entre as diferentes antenas e permite que a taxa de dĂ©bito dos diferentes canais de difusĂŁo (FeMBMS) seja controlada pelo serviço - a capacidade da rede rĂĄdio limita a taxa de transferĂȘncia. Os resultados obtidos no caso de 80000 espectadores que selecionam diferentes feixes ao longo do tempo, considerando 8 estaçÔes base (BS), mostram que a qualidade de experiĂȘncia somente Ă© elevada quando o handover e o controlo da difusĂŁo de feixes pelas BS sĂŁo geridos de acordo com os requisitos da aplicação. A rede recupera a estabilidade apĂłs enormes picos de transferĂȘncia gerindo os seus recursos. Em vez do utilizador ser prejudicado na totalidade quando a rede nĂŁo tem recursos e ser privado de obter serviço, Ă© utilizado um processo alternativo em que a rede diminui a qualidade de multicasting, gastando menos recursos com a mesma quantidade de pedidos. O estado da rede Ă© sempre tido em consideração - embora hajam picos de carga na rede, esta nunca ïŹca congestionada
Network-based IP flow mobility support in 3GPPs evolved packet core
Includes bibliographical references.Mobile data traffic in cellular networks has increased tremendously in the last few years. Due to the costs associated with licensed spectrum, Mobile Network Operators (MNOs) are battling to manage these increased traffic growths. Offloading mobile data traffic to alternative low cost access networks like Wi-Fi has been proposed as a candidate solution to enable MNOs to alleviate congestion from the cellular networks. This dissertation investigates an offloading technique called IP flow mobility within the 3rd Generation Partnership Project (3GPP) all-IP mobile core network, the Evolved Packet Core (EPC). IP flow mobility would enable offloading a subset of the mobile userâs traffic to an alternative access network while allowing the rest of the end-userâs traffic to be kept in the cellular access; this way, traffic with stringent quality of service requirements like Voice over Internet Protocol (VoIP) would not experience service disruption or interruption when offloaded. This technique is different from previous offloading techniques where all the end-userâs traffic is offloaded. IP flow mobility functionality can be realised with either host- or network-based mobility protocols. The recommended IP flow mobility standard of 3GPP is based on the host-based mobility solution, Dual-Stack Mobile IPv6. However, host-based mobility solutions have drawbacks like long handover latencies and produce signaling overhead in the radio access networks, which could be less appealing to MNOs. Network-based mobility solutions, compared to the host-based mobility solutions, have reduced handover latencies with no signaling overhead occurring in the radio access network. Proxy Mobile IPv6 is a networkbased mobility protocol adapted by 3GPP for mobility in the EPC. However, the standardisation of the Proxy Mobile IPv6-based IP flow mobility functionality is still ongoing within 3GPP. A review of related literature and standardisation efforts reveals shortcomings with the Proxy Mobile IPv6 mobility protocol in supporting IP flow mobility. Proxy Mobile IPv6 does not have a mechanism that would ensure session continuity during IP flow handoffs or a mechanism enabling controlling of the forwarding path of a particular IP flow i.e., specifying the access network for the IP flow. The latter mechanism is referred to as IP flow information management and flow-based routing. These mechanisms represent the basis for enabling the IP flow mobility functionality. To address the shortcomings of Proxy Mobile IPv6, this dissertation proposes vi enhancements to the protocol procedures to enable the two mechanisms for IP flow mobility functionality. The proposed enhancements for the session continuity mechanism draw on work in related literature and the proposed enhancements for the IP flow information management and flow-based routing mechanism are based on the concepts used in the Dual- Stack Mobile IPv6 IP flow mobility functionality. Together the two mechanisms allow the end-user to issue requests on what access network a particular IP flow should be routed, and ensure that the IP flows are moved to the particular access network without session discontinuity
Interoperabilidade e mobilidade na internet do futuro
Research on Future Internet has been gaining traction in recent years,
with both evolutionary (e.g., Software Defined Networking (SDN)-
based architectures) and clean-slate network architectures (e.g., Information
Centric Networking (ICN) architectures) being proposed. With
each network architectural proposal aiming to provide better solutions
for specific Internet utilization requirements, an heterogeneous Future
Internet composed by several architectures can be expected, each targeting
and optimizing different use case scenarios. Moreover, the increasing
number of mobile devices, with increasing capabilities and
supporting different connectivity technologies, are changing the patterns
of traffic exchanged in the Internet.
As such, this thesis focuses on the study of interoperability and mobility
in Future Internet architectures, two key requirements that need to be
addressed for the widely adoption of these network architectures. The
first contribution of this thesis is an interoperability framework that,
by enabling resources to be shared among different network architectures,
avoids resources to be restricted to a given network architecture
and, at the same time, promotes the initial roll out of new network
architectures. The second contribution of this thesis consists on the
development of enhancements for SDN-based and ICN network architectures
through IEEE 802.21 mechanisms to facilitate and optimize
the handover procedures on those architectures. The last contribution
of this thesis is the definition of an inter-network architecture mobility
framework that enables MNs to move across access network supporting
different network architectures without losing the reachability to
resources being accessed. All the proposed solutions were evaluated
with results highlighting the feasibility of such solutions and the impact
on the overall communication.A Internet do Futuro tem sido alvo de vĂĄrios estudos nos Ășltimos anos,
com a proposta de arquitecturas de rede seguindo quer abordagens
evolutionĂĄrias (por exemplo, Redes Definidas por Software (SDN))
quer abordagens disruptivas (por exemplo, Redes Centradas na Informação (ICN)). Cada uma destas arquitecturas de rede visa providenciar
melhores soluçÔes relativamente a determinados requisitos de
utilização da Internet e, portanto, uma Internet do Futuro heterogénea
composta por diversas arquitecturas de rede torna-se uma possibilidade,
onde cada uma delas Ă© usada para optimizar diferentes casos
de utilização. Para alĂ©m disso, o aumento do nĂșmero de dispositivos
móveis, com especificaçÔes acrescidas e com suporte para diferentes
tecnologias de conectividade, estå a mudar os padrÔes do tråfego na
Internet.
Assim, esta tese foca-se no estudo de aspectos de interoperabilidade e
mobilidade em arquitecturas de rede da Internet do Futuro, dois importantes
requisitos que necessitam de ser satisfeitos para que a adopção
destas arquitecturas de rede seja considerada. A primeira contribuição
desta tese é uma solução de interoperabilidade que, uma vez que permite
que recursos possam ser partilhados por diferentes arquitecturas
de rede, evita que os recursos estejam restringidos a uma determinada
arquitectura de rede e, ao mesmo tempo, promove a adopção de novas
arquitecturas de rede. A segunda contribuição desta tese consiste
no desenvolvimento de extensÔes para arquitecturas de rede baseadas
em SDN ou ICN através dos mecanismos propostos na norma IEEE
802.21 com o objectivo de facilitar e optimizar os processos de mobilidade
nessas arquitecturas de rede. Finalmente, a terceira contribuição
desta tese é a definição de uma solução de mobilidade envolvendo diferentes
arquitecturas de rede que permite a mobilidade de dispositivos
mĂłveis entre redes de acesso que suportam diferentes arquitecturas de
rede sem que estes percam o acesso aos recursos que estĂŁo a ser acedidos.
Todas as soluçÔes propostas foram avaliadas com os resultados
a demonstrar a viabilidade de cada uma das soluçÔes e o impacto que
tĂȘm na comunicação.Programa Doutoral em InformĂĄtic
Multimedia session continuity in the IP multimedia subsystem : investigation and testbed implementation
Includes bibliographical references (leaves 91-94).The advent of Internet Protocol (IP) based rich multimedia services and applications has seen rapid growth and adoption in recent years, with an equally increasing user base. Voice over IP (VoIP) and IP Television (IPTV) are key examples of services that are blurring the lines between traditional stove-pipe approach network infrastructures. In these, each service required a different network technology to be provisioned, and could only be accessed through a specific end user equipment (UE) technology. The move towards an all-IP core network infrastructure and the proliferation of multi-capability multi-interface user devices has spurred a convergence trend characterized by access to services and applications through any network, any device and anywhere
Exploring intelligent service migration in a highly mobile network
Mobile services allow services to be migrated or replicated closer to users as they move around. This is now regarded as a viable mechanism to provide good Quality of Service to users in highly mobile environments such as vehicular networks. The vehicular environment is rapidly becoming a significant part of the internet and this presents various challenges that must be addressed; this is due to continuous handovers as mobile devices change their point of attachment to these networks resulting in a loss of service. Therefore, this explains the need to build a framework for intelligent service migration. This thesis addresses these issues.
It starts by discussing the requirements for intelligent service migration. Then it investigates a low latency Quality of Service Aware Framework as well as an experimental transport protocol that would be favoured by vehicular networks.
Furthermore, two analytical models are developed using the Zero-Server Markov Chain technique which is a way of analysing scenarios when the server is not continuously available to serve. Using the Zero-Server Markov Chain, the first analytical model looks at lost service due to continuous handovers and the communication dynamics of vehicular networks, while the second model analyses how service migration affects service delivery in these networks. Formulas are developed to yield the average number of packets in the system, the response time, the probability of blocking and a new parameter called the probability of lost service. These formulas are then applied to the Middlesex VANET Testbed to look at reactive and proactive service migration. These techniques are then incorporated into a new Service Management Framework to provide sustainable Quality of Service and Quality of Experience to mobile users in vehicular networks. This thesis also shows that this new approach is better than current approaches as it addresses key issues in intelligent service migration in such environments, and hence can play a significant part in the development of Intelligent Transport Systems for Smart Cities
Remote Control of Unmanned Aerial Vehicles Through the Internet and IEEE 802.11
This dissertation focuses on real-time control of Unmanned Aerial Vehicles (UAVs) through TCP/IP/IEEE 802.11. Using the MAVLink protocol - an open-source protocol for micro air vehicles - a solution that allows the exchange, in real-time, of control messages between a UAV and a remote Control Station was implemented. In order to allow the UAV control by a remote user, the vehicle streams a real-time video feed captured by a video-camera on board. The main challenge of this dissertation is related about the designing and implementation of a fast handover solution that allows an uninterruptible communication
Seer: Empowering Software Defined Networking with Data Analytics
Network complexity is increasing, making network control and orchestration a
challenging task. The proliferation of network information and tools for data
analytics can provide an important insight into resource provisioning and
optimisation. The network knowledge incorporated in software defined networking
can facilitate the knowledge driven control, leveraging the network
programmability. We present Seer: a flexible, highly configurable data
analytics platform for network intelligence based on software defined
networking and big data principles. Seer combines a computational engine with a
distributed messaging system to provide a scalable, fault tolerant and
real-time platform for knowledge extraction. Our first prototype uses Apache
Spark for streaming analytics and open network operating system (ONOS)
controller to program a network in real-time. The first application we
developed aims to predict the mobility pattern of mobile devices inside a smart
city environment.Comment: 8 pages, 6 figures, Big data, data analytics, data mining, knowledge
centric networking (KCN), software defined networking (SDN), Seer, 2016 15th
International Conference on Ubiquitous Computing and Communications and 2016
International Symposium on Cyberspace and Security (IUCC-CSS 2016
D6.2 - Prototype description and field trial results
Deliverable D6.2 del projecte FARAMIRPostprint (published version
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