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1.
This paper proposes a novel framework for virtual content delivery networks (CDNs) based on cloud computing. The proposed framework aims to provide multimedia content delivery services customized for content providers by sharing virtual machines (VMs) in the Infrastructure‐as‐a‐Service cloud, while fulfilling the service level agreement. Furthermore, it supports elastic virtual CDN services, which enables the capabilities of VMs to be scaled to encompass the dynamically changing resource demand of the aggregated virtual CDN services. For this, we provide the system architecture and relevant operations for the virtual CDNs and evaluate the performance based on a simulation.  相似文献   

2.
The widespread use of the Internet has led to the problem of intellectual property and copyright infringement. Digital rights management (DRM) technologies have been developed to protect digital content items. Digital content can be classified into static content (for example, text or media files) and dynamic content (for example, VOD or multicast streams). This paper deals with the protection of a multicast stream on set‐top boxes connected to an IP network. In this paper, we examine the following design and architectural issues to be considered when applying DRM functions to multicast streaming service environments: transparent streaming service and large‐scale user environments. To address the transparency issue, we introduce a ‘selective encryption scheme'. To address the second issue, a ‘key packet insertion scheme’ and ‘hierarchical key management scheme’ are introduced. Based on the above design and architecture, we developed a prototype of a multicasting DRM system. The analysis of our implementation shows that it supports transparent and scalable DRM multicasting service in a large‐scale user environment.  相似文献   

3.
针对多媒体内容的版权保护问题,设计一种新型通用格式多媒体数字版权管理模型,包括内容加密与打包、密钥管理、安全引擎、许可证管理与分发、DRM客户端和DRM管理等功能单元,该模型通过非结构化加密方法,克服了基于内容格式加密方法的局限性,实现对通用格式多媒体内容的保护。另外,采用许可证提取码作为下载许可证的凭证,解决许可证重新发行和转让的问题,并支持细粒度使用控制方式。基于此模型,实现了基于固定与移动融合业务的多媒体数字版权管理系统,并将其运用于数字消费领域,实验结果和实际运行表明该方案不影响多媒体质量,效率及安全性较高,在多媒体内容版权保护方面具有较好的实用性。  相似文献   

4.
This paper describes the scalable extension of High Efficiency Video Coding (HEVC) to provide flexible highquality digital video content services. The proposed scalable codec is designed on multi‐loop decoding architecture to support inter‐layer sample prediction and inter‐layer motion parameter prediction. Inter‐layer sample prediction is enabled by inserting the reconstructed picture of the reference layer (RL) into the decoded picture buffer of the enhancement layer (EL). To reduce the motion parameter redundancies between layers, the motion parameter of the RL is used as one of the candidates in merge mode and motion vector prediction in the EL. The proposed scalable extension can support scalabilities with minimum changes to the HEVC and provide average Bjøntegaard delta bitrate gains of about 24% for spatial scalability and of about 21% for SNR scalability compared to simulcast coding with HEVC.  相似文献   

5.
6.
Media delivery over heterogeneous networks requires both flexible representation and robust protection of content. This paper provides details on the framework for audiovisual content creation, delivery, consumption and protection as conceived within the IST project The Innovative Rights and Access Management Interplatform SolUtion. The proposed framework is based on the emerging MPEG-21 standard for multimedia content delivery and consumption and at the same time it complements it in several aspects, most notably by fully specifying a digital rights management (DRM) scheme. Central to the described framework is a novel key management system, relying on smartcards, which addresses many issues that previously blocked wider adoption of DRM: obtrusiveness of the DRM technology perceived by the end-user, flexibility in licence formulation and adequate level of trust as requested by content owners.  相似文献   

7.
The architecture in a differentiated services (DiffServ) network is based on a simple model that applies a per‐class service in the core node of the network. However, because the network behavior is simple, the network structure and provisioning is complicated. If a service provider wants dynamic provisioning or a better bandwidth guarantee, the differentiated services network must use a signaling protocol with QoS parameters or an admission control method. Unfortunately, these methods increase the complexity. To overcome the problems with complexity, we investigated scalable dynamic provisioning for admission control in DiffServ networks. We propose a new scalable qDPM2 mechanism based on a centralized bandwidth broker and distributed measurement‐based admission control and movable boundary bandwidth management to support heterogeneous QoS requirements in DiffServ networks.  相似文献   

8.
Advances in Digital Video Content Protection   总被引:15,自引:0,他引:15  
The use of digital video offers immense opportunities for creators; however, the ability for anyone to make perfect copies and the ease by which those copies can be distributed also facilitate misuse, illegal copying and distribution ("piracy"), plagiarism, and misappropriation. Popular Internet software based on a peer-to-peer architecture has been used to share copyrighted movies, music, software, and other materials. Concerned about the consequences of illegal copying and distribution on a massive scale, content owners are interested in digital rights management (DRM) systems which can protect their rights and preserve the economic value of digital video. A DRM system protects and enforces the rights associated with the use of digital content. Unfortunately, the technical challenges for securing digital content are formidable and previous approaches have not succeeded. We overview the concepts and approaches for video DRM and describe methods for providing security, including the roles of encryption and video watermarking. Current efforts and issues are described in encryption, watermarking, and key management. Lastly, we identify challenges and directions for further investigation in video DRM.  相似文献   

9.
To solve the increasing popularity of video streaming services over the Internet, recent research activities have addressed the locality of content delivery from a network edge by introducing a storage module into a router. To employ in‐network caching and persistent request routing, this paper introduces a hybrid content delivery network (CDN) system combining novel content routers in an underlay together with a traditional CDN server in an overlay. This system first selects the most suitable delivery scheme (that is, multicast or broadcast) for the content in question and then allocates an appropriate number of channels based on a consideration of the content's popularity. The proposed scheme aims to minimize traffic volume and achieve optimal delivery cost, since the most popular content is delivered through broadcast channels and the least popular through multicast channels. The performance of the adaptive scheme is clearly evaluated and compared against both the multicast and broadcast schemes in terms of the optimal in‐network caching size and number of unicast channels in a content router to observe the significant impact of our proposed scheme.  相似文献   

10.
The Internet is a platform providing connection channels for various services. Whereas for services like email the best‐effort nature of the Internet can be considered sufficient, other services strongly depend on service‐specific connection quality parameters. This quality dependence has led to dedicated content distribution networks as a workaround solution for services like YouTube. Such workarounds are applicable to a small number of services only. With the global application of the Internet, the impact of quality of service varies from annoyance due to jitter in VoIP communication to endangering human lives in telemedicine applications. Thus network connections with end‐to‐end quality guarantees are indispensable for various existing and evolving services. In this paper we consider point‐to‐point multi‐domain network connections for which the end‐to‐end quality has to be assured. Our contribution includes the classification of fault cases in general and countermeasures against end‐to‐end performance degradation. By correlating events and reasonable countermeasures, this work provides the foundation for quality assurance during the operation phase of end‐to‐end connections. We put our contribution in the context of a vision of global‐goal‐aware self‐adaptation in computer networks and outline further research areas that require a similar classification to the work provided here. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

11.
We introduce an advanced terrestrial digital multimedia broadcasting (AT‐DMB) system that overcomes the limitation of data transmission rates of T‐DMB by doubling it with the same frequency bandwidth. In this letter, we propose an efficient algorithm which generates a scalable transport stream in AT‐DMB by multiplexing certain types of elementary streams encoded using scalable video coding and an MPEG‐surround audio coder for high‐quality multimedia services.  相似文献   

12.
Artificial hyperthermia is an emerging technique to induce apoptotic cancer cell death. However, achieving effective hyperthermic apoptosis is often difficult, as cells typically acquire resistance to thermal stress. With the aid of sequential irradiation, highly integrated nanoassemblies based on reduced graphene oxide–ZnO nanoparticles–hyaluronic acid (rGo‐ZnO‐HA) can serve as a multi‐synergistic platform for targeted high‐performance apoptotic cancer therapy. The surface engineering of ZnO/graphene hybrid with multifunctional HA biomacromolecules simultaneously confers the system colloidal stability, biocompatibility, and a cancer cell targeting ability. After receptor‐mediated endocytosis, enzyme‐mediated fluorescence activation helps track cellular uptake and provides truly molecular imaging. Furthermore, the reactive oxygen species (ROS) generated by ZnO/rGo under light illumination can effectively sensitize cancer cells to the subsequent NIR laser‐induced apoptotic hyperthermia. In particular, photo modulation of cellular ROS to sensitize cells provides a novel approach to increase the efficacy of hyperthermic apoptosis. These findings suggest that a powerful apoptotic therapeutic platform could be achieved based on the multi‐synergistic platform.  相似文献   

13.
Today the policy‐based management (PBM) approach is recognized as an efficient solution to simplify the complex task of managing and controlling networks. To this end, the Internet Engineering Task Force (IETF) has introduced a reference framework to build PBM systems. However, this framework only addresses the provisioning of relatively long validity period services based on predefined service‐level agreements. Furthermore, very little work addresses the scalability properties of the instantiation of this framework in a real network. This work aims to extend the IETF PBM framework in order to support dynamic provisioning of short‐term services (end‐system signalling) as well as an instantiation scheme that is scalable (distributed provisioning of edge routers). This instantiation scheme is based on the distribution of the provisioning process while keeping centralized only the parts that involve critical resources, namely bandwidth brokerage. The performance properties of the proposed scheme are then demonstrated throughout both extensive experimentation and an analytical study. The extension of this performance analysis to the case where multiple bandwidth brokers are used is also discussed. The results of this work are intended to be used as a guideline to help network operators to design a scalable PBM system in order to offer to their customers services with quality of service assurance on an on‐demand basis. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

14.
In today's dynamic video landscape, an end user needs services to be delivered to any devices anytime with less delay over the Internet. Now users' expectation has changed; they want faster time‐to‐market, cost reduction, and the ability to adjust according to the evolving requirements, which are a limit for the traditional server‐based approach. The explosive growth of the internet multimedia application needs a new approach to content delivery to overcome the limitations of server‐based techniques. Cloud‐based content delivery networks (CCDNs) have recently started to emerge where contents are cached from the cloud storage and delivered through the distribution service to meet quality of services (QoS) of requested services. In this paper, we dealt with CCDN deployment problem and proposed a new eigenvalue‐based edge infrastructure for a network service provider to serve the users with a variation on proximity interest concerning operational cost and user QoS satisfaction. The edge infrastructure designing is a two‐step process: (a) ideal location search for placing edge server and (b) edge server placement and capacity provisioning. The performance of the proposed approach is appraised via modeling and simulation. Performance evaluation outcomes are exhibited to manifest the effectiveness and competitiveness of our approach when compared with existing algorithms.  相似文献   

15.
We propose a joint optimization network management framework for quality‐of‐service (QoS) routing with resource allocation. Our joint optimization framework provides a convenient way of maximizing the reliability or minimizing the jitter delay of paths. Data traffic is sensitive to droppage at buffers, while it can tolerate jitter delay. On the other hand, multimedia traffic can tolerate loss but it is very sensitive to jitter delay. Depending on the type of data, our scheme provides a convenient way of selecting the parameters which result in either reliability maximization or jitter minimization. We solve the optimization problem for a GPS network and provide the optimal solutions. We find the values of control parameters which control the type of optimization performed. We use our analytical results in a multi‐objective QoS routing algorithm. Finally, we provide insights into our optimization framework using simulations. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

16.
This paper presents a multimedia streaming platform for efficiently transmitting MPEG‐4 content over IP networks. The platform includes an MPEG‐4 compliant streaming server and client, supporting object‐based representation of multimedia scenes, interactivity, and advanced encoding profiles defined by the ISO standard. For scalability purposes, we employ an application‐layer multicast scheme for media transmission using overlay networks. The overlay network, governed by the central entity of the network distribution manager, is dynamically deployed according to a set of pre‐defined criteria. The overlay network supports both broadcast delivery and video‐on‐demand content. The multimedia streaming platform is standards‐compliant and utilizes widespread multimedia protocols such as MPEG‐4, real‐time transport protocol, real‐time transport control protocol, and real‐time streaming protocol. The design of the overlay network was architected with the goal of transparency to both the streaming server and the client. As a result, many commercial implementations that use industry‐standard protocols can be plugged into the architecture relatively painlessly and can enjoy the benefits of the platform.  相似文献   

17.
由于盗版光盘和网络非法下载影片视频的盛行,内容发行商迫切需要采用新的技术来保护合法的视频文件分发。论文提出了一种全新的基于DRM和P2P技术的内容分发模式,采用数字版权管理(DRM)来对视频加密和对用户进行认证,采用P2P技术来低成本快速分发视频文件,收到了良好的效果。  相似文献   

18.
The future wireless communication systems ought to offer high spectral efficiency and flexibility to carry multimedia services with variable rate requirements. The data rate change should be made scalable, continuous and real‐time based to match exactly to what required in different content for conservation of precious bandwidth. The rate change in multiples of two, as implemented in the UMTS W‐CDMA standard, is clearly undesirable. In particular, the multiple access technique itself should support asymmetrical traffic in up‐ and down‐links to fit different connection modes of Internet‐based applications. This paper is to propose an innovative CDMA architecture based on complete complementary (CC) codes, which can address all above concerns. The architecture makes use of ‘offset‐stacked’ spreading modulation, based on which both high spectral efficiency and flexible rate matching are guaranteed. The proposed CC–CDMA system can support continuously alterable data rates, which can match exactly to the user demand without the need of complex ‘rate‐matching’ algorithms. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

19.
In the current trend in telecommunications industry towards all‐internet‐protocol (IP) infrastructures, IP multimedia subsystem (IMS) plays a critical role by providing a coherent data and control‐plane solution for large‐scale live multimedia applications in a flexible and cost‐effective manner. On the other hand, such a large‐scale service platform would inevitably fail without effective support for the quality‐of‐service (QoS) requirements perceived by its users. Among the most important factors that influence user QoS are system performance and scalability. In this paper, a performance model for IMS systems is developed using the queueing Petri nets (QPNs) as the modeling formalism. The model's parameters are tuned based on the measurements carried out using a well‐known IMS implementation. The model is validated against the real system. During the model calibration, the Java garbage‐collector process used in the home subscriber‐server (HSS) implementation was found to be a main factor in the discrepancy between the model and the reality. In addition, the effects of other factors such as the network stack in the operating system are investigated. The validated model is employed to give insights into the scalability of every single instance of IMS implementation. The model is extended to study load balancing among multiple instances of HSS to remove the main bottleneck in the system. It provides a valuable platform for resource management of various components of the IMS ecosystem to support the intended level of QoS for the users.  相似文献   

20.
Spatial audio coding (SAC) is an extremely high compact representation of encoded multi‐channel audio material. This paper suggests a multi‐channel audio service in the terrestrial digital multimedia broadcasting (T‐DMB) system using a novel SAC tool, which is called a virtual source location information (VSLI)‐based SAC tool. Intensive experiments are presented to evaluate the validity of the proposed VSLI‐based SAC tool, and prototypical systems are also presented to demonstrate the reliability of the proposed multi‐channel T‐DMB system in real applications.  相似文献   

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