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Broadcasting, IEEE Transactions on

Issue 2  Part 2 • Date June 2009

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  • [Front cover]

    Page(s): C1
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    Freely Available from IEEE
  • IEEE Transactions on Broadcasting publication information

    Page(s): C2
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  • Table of contents

    Page(s): 309 - 310
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  • From the Guest Editors: IPTV in Multimedia Broadcasting

    Page(s): 311 - 314
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    Freely Available from IEEE
  • An Overview of IPTV Standards Development

    Page(s): 315 - 328
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    In the last few years, IPTV has emerged as one of the major distribution and access techniques for broadband multimedia services. It is one of the primary growth areas for the telecommunications industry. However, existing IPTV systems are generally based on proprietary implementations that do not provide interoperability. Recently, many international standard bodies have published, or are developing, a series of IPTV related standards.. This paper is an overview of the most significant recent and upcoming IPTV standards. View full abstract»

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  • Functional Architecture for NGN-Based Personalized IPTV Services

    Page(s): 329 - 342
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    IPTV is one of the most highly visible services to emerge as part of the development of next generation network (NGN). IPTV services over manageable broadband link from a provider will be one of the ultimate goals of the broadband revolution using NGN. In this paper, we analyze IPTV architecture developed by ITU-T and provide functional architecture for NGN-based IPTV services according to functional mapping between IPTV and NGN. For this, we provide the detailed functional architecture and relevant operations with other functional blocks and present the harmonized architecture between IPTV and NGN for NGN-based IPTV services with the alignment with existing NGN architecture. As challenging architectural issues, we also introduce personalized IPTV services based on Web-based open platform in NGN environment and illustrate functional architecture and service examples for Web-based personalized IPTV services. View full abstract»

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  • Towards an RTP Profile for IPTV

    Page(s): 343 - 352
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (570 KB) |  | HTML iconHTML  

    In this paper we analyze the two major transport protocols that are currently under discussion for IPTV and propose extensions to support convergence. On the one hand, the MPEG-2 transport stream (MPEG2-TS) is well established in the broadcast world, whereas the real-time transport protocol (RTP) is widely adopted in the Internet and mobile world. Our analysis focuses on the timing aspects such as synchronization and buffer management. It is shown that the system target decoder (STD) defined in MPEG2-TS provides a well defined decoder model that allows minimum buffering delay and predictable behavior. In contrast, an RTP receiver is intentionally defined less accurately to allow flexibility for multiple applications. However, this flexibility results in less clear receiver behavior which is a problem for the design and integration of IPTV systems. By comparing the main differences in the timing models of the two protocols we derive additional constraints and definitions for RTP that minimize the difference to MPEG2-TS. It is proposed to specify these changes as part of an RTP/IPTV profile which also defines an RTP system target decoder (RTP-STD). An example for the application of these extensions is a protocol gateway supporting the convergence of broadcast and the Internet world in IPTV. View full abstract»

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  • MAC Layer Multicast Error Control for IPTV in Wireless LANs

    Page(s): 353 - 362
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1082 KB) |  | HTML iconHTML  

    Internet Protocol Television (IPTV) over IEEE 802.11 Wireless LANs, which are considered today as the de-facto wireless access network for local distribution (home networks, hotspots), brings forth a big challenge to guarantee high quality multicast/broadcast delivery over unreliable and time-variant wireless channels. However, in IEEE 802.11 Wireless LANs, current standard MAC layer protocols do not provide any error correction scheme for broadcast/multicast. In our previous work, we enhanced a Leader Based Protocol (LBP) and proposed a Beacon-driven Leader Based Protocol (BLBP) for the MAC layer multicast error control. However, as pure Automatic Repeat reQuest (ARQ) schemes, both LBP and BLBP are not efficient for large multicast groups. In this paper, we combine BLBP and packet level Forward Error Correction (FEC) and propose a Hybrid Leader Based Protocol (HLBP) for the MAC layer multicast error control. HLBP transmits the original data packets using raw broadcast and retransmits parity packets using an improved BLBP which is based on block feedback. To guarantee the required Packet Loss Ratio (PLR) under strict delay constraints for multicast delivery over a Gilbert-Elliott (GE) channel, we analyze LBP, BLBP and HLBP, develop analytic performance models that allow optimizing the configurations. The performance models are verified via simulation experiments. Both the theoretical analysis and simulation results show that HLBP is much more efficient than LBP and BLBP especially for large multicast groups and is also more efficient than the best application layer multicast error correction scheme. BLBP needs the minimum number of redundancy transmissions among all pure ARQ based schemes while HLBP needs the near-minimum number of redundancy transmissions among all schemes. Due to the simplicity and efficiency, BLBP is a good choice for IPTV multicast delivery for small groups in Wireless LANs while HLBP is a better choice for large multicast groups. View full abstract»

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  • IPTV Multicast Over Wireless LAN Using Merged Hybrid ARQ With Staggered Adaptive FEC

    Page(s): 363 - 374
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1711 KB) |  | HTML iconHTML  

    Internet Protocol TV (IPTV), an emerging Internet application, provides more flexibility and interactivity for users because of its embedded return channel. Wireless 802.11 networks, used as the last hop of IPTV networks, would add another dimension of mobility, which is of great value for hot spot deployment and is increasingly required for in-home content distribution. However, a wireless channel may suffer from multi-path fading and interference, which may cause random and burst packet loss and impact users' quality of experience of an IPTV program. We report the design, implementation and evaluation of merged hybrid adaptive FEC and ARQ (MHARQ) system for IPTV multicast over wireless LANs. In MHARQ, an IPTV cache server is introduced to improve the reliability for the last hop wireless distribution. MHARQ combines the advantages of receiver-driven staggered FEC and hybrid ARQ schemes to compensate the large dynamic range of WLAN channels and to achieve high reliability, scalability and wireless bandwidth efficiency for IPTV multicast. We also address backward compatible FEC encoding and decoding, audio and video synchronization issues in practical system implementation. Using the ORBIT radio grid test bed, we have investigated the performance of the proposed MHARQ system with various numbers of users per AP and different numbers of APs per IPTV cache server. It is demonstrated via real system implementation on ORBIT that MHARQ improves wireless bandwidth efficiency and scalability for reliable IPTV multicast, compared with existing reliable multicast schemes. View full abstract»

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  • Reactive Estimation of Packet Loss Probability for IP-Based Video Services

    Page(s): 375 - 385
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1062 KB) |  | HTML iconHTML  

    The advent of IP/MPLS based networks allows providers to implement integrated services packet network (ISPN) concepts for IPTV applications. IPTV systems require a high level of quality of service (QoS) in order to win customers which are subscribed with cable companies. Packet loss probability is one of the primary QoS parameters whose value affects the user experience and which provides a quantitative measure for customers' perception of the QoS factor in practical networks. Therefore, the online accurate measurement and estimation of the packet loss probability is a key issue to be addressed. Furthermore, the packet loss probability provides the feedback information which can be used in the network based control system to maintain it at a prescribed and negotiated value. In this paper, a reactive estimator (RE) of the packet loss probability is constructed. As all parameters related to the network traffic, the packet loss is a non-linear and non-Gaussian stochastic process. The proposed RE has the capability to adapt to variable stochastic contexts by employing one dynamic item based on the feedback of the real-time loss ratio measurement. A series of experiments are devised on a live network to evaluate the performance of the estimator under multiple traffic arrival models and within various buffer sizes. The numeric results show that the practical estimator is accurate enough to approximate the packet loss probability, such that it can be further used as a feedback parameter in a closed control loop which can keep the packet loss probability close to a prescribed value. View full abstract»

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  • Preserving Video Quality in IPTV Networks

    Page(s): 386 - 395
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1574 KB) |  | HTML iconHTML  

    Growing numbers of service providers are implementing video services over IP networks, and discovering the unique challenges of providing a high quality-of-experience (QoE) to subscribers. Delivering consistent QoE in packet-switched networks can be a complex proposition due to the high sensitivity of video traffic to packet loss, as well as to delay and jitter. Preserving video quality in IP Television (IPTV) networks that mostly rely on copper access lines poses an even greater challenge. Service providers need intelligent mechanisms in core and distribution networks to prevent congestion that deteriorates video quality, as well as intelligence between the aggregation networks and IP set-top box (STB) to repair packet losses, speed up channel change times and monitor the quality of the subscriber experience. This paper discusses a series of core and aggregation-layer approaches, collectively referred to as Visual Quality of Experience (VQE) to address these issues. The VQE approach encompasses on-path video connection admission control (CAC) employing Resource ReSerVation Protocol (RSVP) in the core and aggregation layers, and a real-time signaling mechanism operating between the provider aggregation edge and the IP STBs to address packet losses, long channel change times and quality monitoring. View full abstract»

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  • Application Layer FEC for Mobile TV Delivery in IP Datacast Over DVB-H Systems

    Page(s): 396 - 406
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    In this paper we investigate the potential gain that can be obtained in DVB-H using application layer forward error correction (AL-FEC) to perform a multi-burst protection of the transmission for improving the reception of streaming services for mobile terminals. Compared to the conventional approach with link layer multi protocol encapsulation FEC (MPE-FEC), this technique allows to increase the robustness of the DVB-H transmission not only as a function of the capacity devoted for error repair (FEC overhead), but also as a function of the number of bursts jointly encoded. The main drawback of this approach is an increase of the network latency, that can be translated into a larger service access time, and, in the case of mobile TV, a larger zapping time between channels, which is currently seen as a crucial parameter for DVB-H usability. In this paper the performance of the proposed approach is evaluated using field measurements. We evaluate the gain compared to MPE-FEC in terms of reduced IP packet error rate of the streaming service as a function of the FEC overhead and the latency introduced. Moreover, simulations have been performed to quantify feasible link margin gains. We also discuss techniques to reduce and hide the zapping time from the perception of the users. View full abstract»

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  • Analysis and Improvements of Zapping Times in IPTV Systems

    Page(s): 407 - 418
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (872 KB) |  | HTML iconHTML  

    IPTV is becoming a serious alternative to traditional broadcast schemes, such as cable, satellite or terrestrial, to deliver TV to the home. However, the expectation of the user is that IPTV provides the same or even better quality of experience (QoE). An important part of QoE for linear TV services is the channel change time (CCT) also known as zapping time. Due to its relevance many ideas and concepts have been published which describe how to optimize or speed up the CCT. First, to be able to judge the challenges and benefits of the available concepts, a common understanding of the contributors to the CCT is necessary. This article provides an overview of all elements in the IPTV end-to-end chain influencing the CCT from the head end down to the set-top box (STB) and finally to the display. Second, various techniques for reducing the CCT are presented and discussed. View full abstract»

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  • Integrated Digital Rights Management for Mobile IPTV Using Broadcasting and Communications

    Page(s): 419 - 424
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (938 KB) |  | HTML iconHTML  

    This paper presents a digital rights management (DRM) scheme for mobile broadcasting that integrates management via broadcasting and communications. The scheme provides access control and rights protection for subscription Mobile IPTV (Internet Protocol TV), enabling transmission of contract information to control broadcasting reception via both broadcasting wave and communications. It has transmission functions that reduce the amount of contract information that has to be transmitted through broadcasting as well as a function for transmitting contract information via communications. A PC simulation indicates that the DRM scheme is effective in terms of the transmission rate required to send contract information via broadcasting wave. We also demonstrated the feasibility of the DRM scheme by using a prototype system implemented on an SIM card. The DRM scheme enables advanced mobile receiver functions such as pay-per-view with an interactivity channel using communications and a subscription TV such as pay-per-month on mobile receivers without an interactivity channel by transmitting contract information via broadcasting wave. View full abstract»

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  • Content and Service Protection for IPTV

    Page(s): 425 - 436
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    Content or service delivered through IPTV is high quality and of high economic value accordingly. As digital technologies progress, illegal copy and redistribution of IPTV content become easier and simpler. Therefore it is required to protect IPTV content or service. In this paper, following the approaches taken by ITU-T IPTV Focus Group, we analyze the security threats and requirements. We also discuss related issues and solutions for IPTV. Specially, interoperability issues among different content and service protection systems are addressed. View full abstract»

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  • SASHA—A Quality-Oriented Handover Algorithm for Multimedia Content Delivery to Mobile Users

    Page(s): 437 - 450
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1682 KB) |  | HTML iconHTML  

    The convergence of the existing network access technologies to a common IP-based architecture and the increase in popularity of accessing video content over the Internet makes IPTV a promising solution for media and entertainment industries. Additionally, video content delivery to the increasingly popular mobile devices over heterogeneous wireless networks makes IPTV even more appealing. However the distribution of multimedia content over heterogeneous wireless networks to mobile devices involves significant technical challenges related to mobility management and quality of service provisioning. The existing solutions do not consider quality of service as a decision making parameter for mobility management in general and handover management in particular. This paper proposes the smooth adaptive soft handover algorithm (SASHA), a novel quality-aware approach to handover based on load balancing among different networks using a comprehensive, quality of multimedia streaming (QMS), function for decision making. SASHA represents the handover management solution at the core of the more comprehensive multimedia mobility management system (M3S), a quality oriented mobility management framework for multimedia applications which maximizes user perceived quality by efficiently exploiting all available communication resources. Simulation-based testing results are presented, outlining the performance of SASHA in different mobility scenarios. The evaluation is performed for different number of nodes performing handover simultaneous and for various situations in terms of networks' overlapping area. The results shown indicate how SASHA outperforms other three mobility management solutions in terms of quality, scalability and resilience to the dynamics of the networks' overlapping area. View full abstract»

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  • A Post-Admission Control Approach in Wireless Home Networks

    Page(s): 451 - 459
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    The subject of quality of service (QoS) and admission control for wireless home networks is of great interest now for both research and industry communities. Many standard developing organizations consider admission control as the only means to prevent overload of the network and a basis of a well thought through QoS solution. In this paper, we present a post-admission control solution for wireless home networks. By analysing the traffic load of the network the admission control decisions are made with respect to the already running applications. With the help of a dynamic prioritization mechanism coupled with the policy-based user-centric QoS solution, the presented approach provides flexible regulation of traffic on the network and improves the overall user experience. View full abstract»

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  • A Broadcasting Scheme for Selective Contents Considering Available Bandwidth

    Page(s): 460 - 467
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (508 KB) |  | HTML iconHTML  

    Due to the recent popularization of digital broadcasting systems, selective contents, i.e., watching contents selected by users themselves, have attracted great attention. For example, in a news program, after a user selects an interesting content, he/she watches it. In selective contents broadcasting, since the server needs to deliver many contents, the necessary bandwidth for continuously playing the data increases. Conventional schemes reduce the necessary bandwidth by producing an effective broadcast schedule. However, they do not consider the upper limit in the bandwidth. When an upper limit exists in the bandwidth, users may wait to play the data. In this paper, we propose a broadcasting scheme that reduces waiting time by considering available bandwidth. In our proposed scheme, by acquiring the channel bandwidth that is the same as the data consumption rate, we effectively reduce the waiting time. View full abstract»

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  • Adaptive Hybrid Transmission Mechanism for On-Demand Mobile IPTV Over WiMAX

    Page(s): 468 - 477
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    In this paper, we propose an Adaptive Hybrid Transmission (AHT) scheme for on-demand mobile IPTV service over broadband wireless access network (i.e. mobile WiMAX, 802.16e). Proposed algorithm utilizes hybrid mechanism which combines multi-channel multicasting and unicast scheme to enhance not only service blocking probability but also reduce overall bandwidth consumption of the wireless system which has very limited resources compared to wired networks. An adaptive resource allocation algorithm is also proposed, and is shown to achieve minimum blocking probability. In order to evaluate the performance, we compare proposed algorithm against traditional unicast and multicast schemes. View full abstract»

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  • On the Enforcement of Quality of Service Policies for IPTV Service Offerings

    Page(s): 478 - 484
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (429 KB) |  | HTML iconHTML  

    This paper discusses both Quality of Service (QoS) information signaling and IPTV traffic engineering options that may serve as key components of IPTV service-specific QoS policies, which are designed to accommodate with customers' requirements and constraints (such as access capabilities) as well as ever-changing networking conditions that may possibly affect the level of quality associated to the delivery of such services. View full abstract»

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  • Continuous Adaptation Enhancement in Linear Regression Algorithm for Clock Recovery in IPTV Environment

    Page(s): 485 - 490
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (945 KB) |  | HTML iconHTML  

    This paper presents a new technique for Clock Recovery in MPEG-2 Transport Streams in DVB-IPTV environment. The amount of jitter in this environment is very high compared to DVB-S or DVB-T. Use of linear regression algorithm for clock synchronization over packet switched networks is suggested by researchers in the similar field. However, the stability of such a filter in real time set top box application posed a problem. The continuous adaptive feedback loop used with the linear regression algorithm provides accurate clock synchronization even when subjected to jitter of half a second. This robustness is needed for IP environment because of the increasing network traffic. The algorithm was simulated and found to require low computation time, high jitter attenuation and fast response as needed for the IP network. It is auto-adaptive for both low and high jitter environments by analysing the jitter present in the stream. The algorithm was implemented for real time application in IPTV set top box and tested to be stable in the RTOS environment. View full abstract»

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  • Performance of Caching Algorithms for IPTV On-Demand Services

    Page(s): 491 - 501
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (969 KB) |  | HTML iconHTML  

    Due to its native return channel and its ability to easily address each user individually an IPTV system is very well suited to offer on-demand services. Those services are becoming more popular as there is an undeniable trend that users want to watch the offered content when and where it suits them best. Because multicast can no longer be relied upon for such services, as was the case when offering linear-programming TV, this trend risks to increase the traffic unwieldy over some parts of the IPTV network unless caches are deployed in strategic places within it. Since caches are limited in size and the popularity of on-demand content is volatile (i.e., changing over time), it is not straightforward to decide which objects to cache at which moment in time. This paper introduces and studies a caching algorithm that tracks the popularity of objects to make intelligent caching decisions. We will show that when its parameters are set equal or close to their optimal values this algorithm outperforms traditional algorithms as LRU (least-recently used) and LFU (least-frequently used). After a generic study of the algorithm fed by a user demand model that takes the volatility of the objects into account we will discuss two particular cases of an on-demand service, video-on-demand and catch-up TV, for each of which we give guidelines on how to dimension their associated caches. View full abstract»

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  • Audience Measurement Modeling for Convergent Broadcasting and IPTV Networks

    Page(s): 502 - 515
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1696 KB) |  | HTML iconHTML  

    Audience research is a vital part of TV and radio broadcasting, as well as of the more recent forms of media content delivery, such as the Internet, IPTV, mobile phones, Personal Video Recorders (PVRs) and portable media viewers. The uses of audience research range from self-promotion to refining service offerings and setting advertising rates. Without reliable audience data, many businesses will be reluctant to participate in the new platforms. This paper describes an end-to-end system for convergent audience measurement focused on IPTV but covering also terrestrial, cable, satellite and mobile broadcasting. We created the audience measurement system from the elaboration of a logical architectural model and a common data model which can be applied to any media scenario. We implemented this logical and data model in stationary and mobile media receivers (in the paper the particular case of IPTV is extensively explained). In addition user consumption is modeled and metrics are provided for user media consumption profiling and impact quantification in IPTV environments. View full abstract»

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  • Performance-Aware Replication of Distributed Pre-Recorded IPTV Content

    Page(s): 516 - 526
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (937 KB) |  | HTML iconHTML  

    Video recording in IPTV systems is a promising service that provides time-shifted services in relation to storing TV content closer to user devices such as set-top boxes. Existing approaches do not support collaboration between nodes which have correlated contents, a fact that can affect the performance of the overall system. To make this service more interactive and proactive, this paper presents the architecture using the smart personal information network (Smart PIN) as a novel performance-based content sharing network for IPTV content which uses a user-centric utility-based multimedia data replication scheme (MDRS). This allows the exchange of data based on both network performance and user interest in exchanged multimedia content in order to achieve efficient content sharing. The proposed solution is evaluated through extensive simulations and results show much improved behavior in comparison with two other existing general purpose data replication schemes. View full abstract»

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  • Scalable Video Coding for IPTV Services

    Page(s): 527 - 538
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    Scenarios for the use of the recently approved scalable video coding (SVC) extension of H.264/MPEG4-AVC in IPTV services are presented. For that, a brief technical overview of SVC when deployed in IPTV services is provided. The coding efficiency of the various scalability types of SVC is demonstrated followed by an analysis of the complexity of the various SVC tools. Based on this technical characterization, it is described how the different SVC features such as efficient methods for graceful degradation, bit rate adaptation, and format adaptation, can be mapped to application requirements of IPTV services. It is discussed how such mappings can lead to improved content portability, management and distribution as well as an improved management of access network throughput resulting in better quality of service and experience for the users of IPTV services. View full abstract»

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Aims & Scope

IEEE Transactions on Broadcasting covers the field of broadcast technology, including the production, distribution, transmission, and propagation aspects of broadcasting.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Yiyan Wu
Communications Research Ctr Canada