3,265 research outputs found
Recommended from our members
Multimedia delivery in the future internet
The term âNetworked Mediaâ implies that all kinds of media including text, image, 3D graphics, audio
and video are produced, distributed, shared, managed and consumed on-line through various networks,
like the Internet, Fiber, WiFi, WiMAX, GPRS, 3G and so on, in a convergent manner [1]. This white
paper is the contribution of the Media Delivery Platform (MDP) cluster and aims to cover the Networked
challenges of the Networked Media in the transition to the Future of the Internet.
Internet has evolved and changed the way we work and live. End users of the Internet have been confronted
with a bewildering range of media, services and applications and of technological innovations concerning
media formats, wireless networks, terminal types and capabilities. And there is little evidence that the pace
of this innovation is slowing. Today, over one billion of users access the Internet on regular basis, more
than 100 million users have downloaded at least one (multi)media file and over 47 millions of them do so
regularly, searching in more than 160 Exabytes1 of content. In the near future these numbers are expected
to exponentially rise. It is expected that the Internet content will be increased by at least a factor of 6, rising
to more than 990 Exabytes before 2012, fuelled mainly by the users themselves. Moreover, it is envisaged
that in a near- to mid-term future, the Internet will provide the means to share and distribute (new)
multimedia content and services with superior quality and striking flexibility, in a trusted and personalized
way, improving citizensâ quality of life, working conditions, edutainment and safety.
In this evolving environment, new transport protocols, new multimedia encoding schemes, cross-layer inthe
network adaptation, machine-to-machine communication (including RFIDs), rich 3D content as well as
community networks and the use of peer-to-peer (P2P) overlays are expected to generate new models of
interaction and cooperation, and be able to support enhanced perceived quality-of-experience (PQoE) and
innovative applications âon the moveâ, like virtual collaboration environments, personalised services/
media, virtual sport groups, on-line gaming, edutainment. In this context, the interaction with content
combined with interactive/multimedia search capabilities across distributed repositories, opportunistic P2P
networks and the dynamic adaptation to the characteristics of diverse mobile terminals are expected to
contribute towards such a vision.
Based on work that has taken place in a number of EC co-funded projects, in Framework Program 6 (FP6)
and Framework Program 7 (FP7), a group of experts and technology visionaries have voluntarily
contributed in this white paper aiming to describe the status, the state-of-the art, the challenges and the way
ahead in the area of Content Aware media delivery platforms
Transforming Energy Networks via Peer to Peer Energy Trading: Potential of Game Theoretic Approaches
Peer-to-peer (P2P) energy trading has emerged as a next-generation energy
management mechanism for the smart grid that enables each prosumer of the
network to participate in energy trading with one another and the grid. This
poses a significant challenge in terms of modeling the decision-making process
of each participant with conflicting interest and motivating prosumers to
participate in energy trading and to cooperate, if necessary, for achieving
different energy management goals. Therefore, such decision-making process
needs to be built on solid mathematical and signal processing tools that can
ensure an efficient operation of the smart grid. This paper provides an
overview of the use of game theoretic approaches for P2P energy trading as a
feasible and effective means of energy management. As such, we discuss various
games and auction theoretic approaches by following a systematic classification
to provide information on the importance of game theory for smart energy
research. Then, the paper focuses on the P2P energy trading describing its key
features and giving an introduction to an existing P2P testbed. Further, the
paper zooms into the detail of some specific game and auction theoretic models
that have recently been used in P2P energy trading and discusses some important
finding of these schemes.Comment: 38 pages, single column, double spac
FLAIM: A Multi-level Anonymization Framework for Computer and Network Logs
FLAIM (Framework for Log Anonymization and Information Management) addresses
two important needs not well addressed by current log anonymizers. First, it is
extremely modular and not tied to the specific log being anonymized. Second, it
supports multi-level anonymization, allowing system administrators to make
fine-grained trade-offs between information loss and privacy/security concerns.
In this paper, we examine anonymization solutions to date and note the above
limitations in each. We further describe how FLAIM addresses these problems,
and we describe FLAIM's architecture and features in detail.Comment: 16 pages, 4 figures, in submission to USENIX Lis
On M2M Micropayments : A Case Study of Electric Autonomous Vehicles
The proliferation of electric vehicles has spurred the research interest in
technologies associated with it, for instance, batteries, and charging
mechanisms. Moreover, the recent advancements in autonomous cars also encourage
the enabling technologies to integrate and provide holistic applications. To
this end, one key requirement for electric vehicles is to have an efficient,
secure, and scalable infrastructure and framework for charging, billing, and
auditing. However, the current manual charging systems for EVs may not be
applicable to the autonomous cars that demand new, automatic, secure,
efficient, and scalable billing and auditing mechanism. Owing to the
distributed systems such as blockchain technology, in this paper, we propose a
new charging and billing mechanism for electric vehicles that charge their
batteries in a charging-on-the-move fashion. To meet the requirements of
billing in electric vehicles, we leverage distributed ledger technology (DLT),
a distributed peer-to-peer technology for micro-transactions. Our
proof-of-concept implementation of the billing framework demonstrates the
feasibility of such system in electric vehicles. It is also worth noting that
the solution can easily be extended to the electric autonomous cars (EACs)
Discussion on drivers and proposition of approaches to support the transition of traditional electricity consumers to prosumers
In recent years, traditional power systems have undergone a significant transition, mainly
related to the massive penetration of Renewable Energy Sources (RES). More specifically, the
transformation of residential consumers into prosumers has been challenging to the traditional
operation of electricity markets. This transition brings new challenges and opportunities to
the power system, leading to new Business Model (BM). One widely discussed change is
related to a consumer-centric or prosumer-driven approach, promoting increased participation
of small consumers in power systems. The present thesis aims at discussing the recent BMs as
enablers of the increasing prosumersâ role in the energy market and power system worldwide,
deepening the discussion with a holistic view of the Brazilian context. To do so, it defines
the main features of prosumers and their general related regulation as well as possible market
designs within power systems. Moreover, the work intends to contribute to the knowledge,
identification and understanding of the main regulatory barriers and enablers for the development
of those BMs in the Brazilian energy market. In addition, it discusses enabling technologies to
properly create the conditions that sustain new prosumer-driven markets. Then, it presents a
comprehensive review of existing and innovative BMs and a discussion on their future roles in
modern power systems and, in the Brazilian regulatory framework seeking to guide the decisions
for the country to develop its political and regulatory environment in the future. Moreover, a
set of recommendations for promoting these BMs in the power system worldwide is provided
along with policy recommendations to promote prosumers aggregation in the Brazilian energy
sector. An important conclusion is that, even though economically possible, not all innovative
BMs can spread around the world due to regulatory issues. Seeking to further explore one of
the prosumer-driven approaches presented and the challenges imposed by this innovative BM,
a study of energy and reserve markets based on the Peer-to-Peer (P2P) structure is carried out.
This structure is very promising for the prosumersâ promotion but presents some challenges for
the network operation. A critical challenge is to ensure that network constraints are not violated
due to energy trades between peers and neither due to the use of reserve capacity. Therefore,
two methodologies are proposed. First, is proposed a three-step approach (P2PTDF), using
Topological Distribution Factors (TDF) to penalize peers responsible for violations that may
occur in the network constraints, ensuring a feasible solution. Second, it is proposed a new
integrated prosumers-DSO approach applied in P2P energy and reserve tradings that also ensures
the feasibility of both energy and reserve transactions under network constraints. The proposed
approach includes the estimation of reserve requirements based on the RES uncertain behavior
from historical generation data, which allows identifying RES patterns. The proposed models
are assessed through a case study that uses a 14-bus system, under the technical and economic
criteria. The results show that the approaches can ensure a feasible network operation.Nos Ășltimos anos, os sistemas tradicionais de energia passaram por uma transição significativa, principalmente relacionada Ă penetração massiva de fontes de energia renovĂĄveis (do
inglĂȘs, Renewable energy sources-RES). Mais especificamente, a transformação de consumidores
residenciais em prosumidores tem desafiado a atual operação do mercado de energia elétrica.
Essa transição traz novos desafios e oportunidades para o sistema elétrico, levando a novos
modelos de negĂłcios (do inglĂȘs, Business Models-BM). Uma mudança amplamente discutida
estĂĄ relacionada a uma abordagem centrada no consumidor ou direcionada ao prossumidor,
promovendo maior participação de pequenos consumidores nos sistemas de energia. A presente
tese tem como objetivo discutir os recentes BMs como facilitadores do crescente papel dos
prosumidores no mercado de energia e no sistema elétrico mundial, aprofundando a discussão
com uma visĂŁo holĂstica do contexto brasileiro. Para tanto, define as principais caracterĂsticas
dos prosumidores e sua regulamentação geral relacionada, bem como possĂveis designs de
mercado dentro dos sistemas de energia. Além disso, o trabalho pretende contribuir para o
conhecimento, identificação e compreensão das principais barreiras regulatórias e facilitadoras
para o desenvolvimento desses BMs no mercado brasileiro de energia. Assim como, discutir as
tecnologias importantes para criar adequadamente as condiçÔes que sustentam novos mercados
orientados ao consumidor final. Em seguida, apresenta uma revisão abrangente dos BMs existentes e inovadores e uma discussão sobre seus papéis futuros nos sistemas de energia modernos
e, no quadro regulatĂłrio brasileiro, buscando orientar as decisĂ”es para que o paĂs desenvolva
seu ambiente polĂtico e regulatĂłrio no futuro. AlĂ©m disso, um conjunto de recomendaçÔes
para promover esses BMs no sistema de energia em todo o mundo Ă© fornecido juntamente com
recomendaçÔes de polĂticas para promover a agregação de prosumidores no setor de energia
brasileiro. Uma conclusĂŁo importante Ă© que, mesmo sendo economicamente possĂvel, nem todos
os BMs inovadores podem se espalhar pelo mundo devido a obstĂĄculos regulatĂłrias. Buscando
explorar ainda mais uma das abordagens orientadas ao prosumidor apresentadas e os desafios
impostos por este BM inovador, Ă© realizado um estudo dos mercados de energia e de reserva com
base na estrutura ponto a ponto (do inglĂȘs, peer-to-peer-P2P). Esta estrutura Ă© muito promissora
para a promoção dos prosumidores mas apresenta alguns desafios para o funcionamento da rede.
Um desafio crĂtico Ă© garantir que as restriçÔes da rede nĂŁo sejam violadas devido a negociaçÔes
de energia entre pares e nem devido ao uso da capacidade de reserva. Portanto, duas metodologias sĂŁo propostas. Primeiramente, Ă© proposta uma abordagem em trĂȘs passos (P2PTDF),
utilizando Fatores de Distribuição TopolĂłgica (do inglĂȘs, Topological Distribution Factors-TDF
) para penalizar os peers responsåveis por violaçÔes que possam ocorrer nas restriçÔes da rede,
garantindo uma solução viåvel. Em segundo lugar, é proposta uma nova abordagem integrada
de prosumidores-DSO aplicada em transaçÔes P2P de energia e reserva que também garante a
viabilidade de transaçÔes de energia e reserva sob restriçÔes de rede. A abordagem proposta
inclui a estimativa dos requisitos de reserva com base no comportamento incerto da RES a partir
de dados históricos de geração, o que permite identificar padrÔes de RES. Os modelos propostos
são avaliados através de um estudo de caso que utiliza um sistema de 14 barras, sob os critérios
técnico e econÎmico. Os resultados mostram que as abordagens podem garantir uma operação
de rede viĂĄvel abrangendo energia e mercados de reserva
Assured information sharing for ad-hoc collaboration
Collaborative information sharing tends to be highly dynamic and often ad hoc among organizations. The dynamic natures and sharing patterns in ad-hoc collaboration impose a need for a comprehensive and flexible approach to reflecting and coping with the unique access control requirements associated with the environment.
This dissertation outlines a Role-based Access Management for Ad-hoc Resource Shar- ing framework (RAMARS) to enable secure and selective information sharing in the het- erogeneous ad-hoc collaborative environment. Our framework incorporates a role-based approach to addressing originator control, delegation and dissemination control. A special trust-aware feature is incorporated to deal with dynamic user and trust management, and a novel resource modeling scheme is proposed to support fine-grained selective sharing of composite data. As a policy-driven approach, we formally specify the necessary pol- icy components in our framework and develop access control policies using standardized eXtensible Access Control Markup Language (XACML). The feasibility of our approach is evaluated in two emerging collaborative information sharing infrastructures: peer-to- peer networking (P2P) and Grid computing. As a potential application domain, RAMARS framework is further extended and adopted in secure healthcare services, with a unified patient-centric access control scheme being proposed to enable selective and authorized sharing of Electronic Health Records (EHRs), accommodating various privacy protection requirements at different levels of granularity
A Peer-to-Peer Network Framework Utilising the Public Mobile Telephone Network
P2P (Peer-to-Peer) technologies are well established and have now become accepted as a mainstream networking approach. However, the explosion of participating users has not been replicated within the mobile networking domain. Until recently the lack of suitable hardware and wireless network infrastructure to support P2P activities was perceived as contributing to the problem. This has changed with ready availability of handsets having ample processing resources utilising an almost ubiquitous mobile telephone network. Coupled with this has been a proliferation of software applications written for the more capable `smartphone' handsets. P2P systems have not naturally integrated and evolved into the mobile telephone ecosystem in a way that `client-server' operating techniques have. However as the number of clients for a particular mobile application increase, providing the `server side' data storage infrastructure becomes more onerous. P2P systems offer mobile telephone applications a way to circumvent this data storage issue by dispersing it across a network of the participating users handsets.
The main goal of this work was to produce a P2P Application Framework that supports developers in creating mobile telephone applications that use distributed storage. Effort was assigned to determining appropriate design requirements for a mobile handset based P2P system. Some of these requirements are related to the limitations of the host hardware, such as power consumption. Others relate to the network upon which the handsets operate, such as connectivity. The thesis reviews current P2P technologies to assess which was viable to form the technology foundations for the framework. The aim was not to re-invent a P2P system design, rather to adopt an existing one for mobile operation. Built upon the foundations of a prototype application, the P2P framework resulting from modifications and enhancements grants access via a simple API (Applications Programmer Interface) to a subset of Nokia `smartphone' devices. Unhindered operation across all mobile telephone networks is possible through a proprietary application implementing NAT (Network Address Translation) traversal techniques.
Recognising that handsets operate with limited resources, further optimisation of the P2P framework was also investigated. Energy consumption was a parameter chosen for further examination because of its impact on handset participation time.
This work has proven that operating applications in conjunction with a P2P data storage framework, connected via the mobile telephone network, is technically feasible. It also shows that opportunity remains for further research to realise the full potential of this data storage technique
A framework for the dynamic management of Peer-to-Peer overlays
Peer-to-Peer (P2P) applications have been associated with inefficient operation, interference with other network services and large operational costs for network providers. This thesis presents a framework which can help ISPs address these issues by means of intelligent management of peer behaviour. The proposed approach involves limited control of P2P overlays without interfering with the fundamental characteristics of peer autonomy and decentralised operation.
At the core of the management framework lays the Active Virtual Peer (AVP). Essentially intelligent peers operated by the network providers, the AVPs interact with the overlay from within, minimising redundant or inefficient traffic, enhancing overlay stability and facilitating the efficient and balanced use of available peer and network resources. They offer an âinsiderâsâ view of the overlay and permit the management of P2P functions in a compatible and non-intrusive manner. AVPs can support multiple P2P protocols and coordinate to perform functions collectively.
To account for the multi-faceted nature of P2P applications and allow the incorporation of modern techniques and protocols as they appear, the framework is based on a modular architecture. Core modules for overlay control and transit traffic minimisation are presented. Towards the latter, a number of suitable P2P content caching strategies are proposed.
Using a purpose-built P2P network simulator and small-scale experiments, it is demonstrated that the introduction of AVPs inside the network can significantly reduce inter-AS traffic, minimise costly multi-hop flows, increase overlay stability and load-balancing and offer improved peer transfer performance
- âŠ