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Single carrier frequency-domain equalization (SC-FDE) modulations are known to be suitable for broadband wireless communications due to their robustness against severe time-dispersion effects and the relatively low envelope fluctuations of the transmitted signals. In this paper, we consider the use of SC-FDE schemes in broadcasting systems. A single frequency network transmission is assumed, and we study the impact of distinct carrier frequency offset (CFO) between the local oscillator at each transmitter and the local oscillator at the receiver. We propose an efficient method for estimating the channel frequency response and CFO associated to each transmitter and propose receiver structures able to compensate the equivalent channel variations due to different CFO for different transmitters. Our performance results show that we can have excellent performance, even when transmitters have substantially different frequency offsets. [ABSTRACT FROM AUTHOR]

This paper investigates deploying a village level community radio application on an ad hoc network substrate comprising completely of basic mobile phones. We envision a system where any user in the network is equally empowered to generate and distribute audio content to the entire network, using his or her mobile phone. The paper focuses on the study of suitable broadcast algorithms for such a network. In this context we propose a novel broadcast technique called MaBA (Memory-aided Broadcast Algorithm) where nodes bank on their memory to decide whether to forward packets of an audio stream — capitalizing on their past behavior to stabilize on fixed routes for the entire stream. In our scheme called Environs Aware Broadcast Mechanism (EABA), a node gauges the local mobility around itself and uses that to decide which of two broadcast mechanisms to use. When mobility is high it uses SBA (Scalable Broadcast Algorithm), a well-known neighbor knowledge broadcast algorithm with relatively high overheads; but when mobility is low it switches to MaBA. Extensive simulations on a village level MANET confirm that EABA is successful in substantially reducing jitter, latency and packet loss: all critical metrics for an audio application. At the same time EABA does not incur other overheads and maintains the same levels of reachability and efficiency as SBA. [ABSTRACT FROM PUBLISHER]

This paper proposes a new approach to avoiding collisions for broadcast packets in distributed wireless LANs. The basic idea is to use in-band pulses to convey the medium access control information for broadcast packets. The new approach extends the basic functionality of the IEEE 802.11 distributed coordination function (DCF) from the unicast case to the broadcast case and significantly improves the broadcasting efficiency in wireless LANs. [ABSTRACT FROM PUBLISHER]

In this paper, we study the impact of obstacles (such as buildings) in the radio propagation in the urban vehicular network's environment. The impact has been realized not only by the network-level performance metrics, but also by the application-level performance metrics. A majority of the existing works consider perfect physical layer, which ignores the impact of path loss and shadowing effect in radio propagation caused by the urban canyon. First, we show that ignoring the impact of obstacles in radio propagation provides very high superficial network-level performance. Second, under obstacle shadowing, we perform analytical analysis and Ns-3 based realistic urban vehicular simulation of current dedicated short-range communication based safety message broadcasting to study the achievable performance of application-level performance metrics. This study reveals the answer of the key question, whether the achieved network-level performance metric is good enough for the safety-critical applications under the acute attenuation in radio propagation in urban environment. Third, we propose opportunistic vehicle-assisted or dedicated road side unit-assisted network coded relaying for improving reliability at road intersection. Simulation results show that the proposed approach improves more than 65% reliability for delay sensitive and around 25% reliability for less delay sensitive applications at intersections. [ABSTRACT FROM AUTHOR]

Single-frequency networks (SFN) are widely adopted in terrestrial broadcast networks based on high-power high-tower (HPHT) deployments. The mobile broadcasting standard Evolved Multimedia Broadcast Multicast Service (eMBMS) has been enhanced in Release 14 to enable SFN operation with larger CP duration which may allow for the deployment of large area SFNs and even the combined operation between HPHT and low-power low-tower (LPLT) cellular stations. The knowledge of the signal-to-interference-plus-noise ratio (SINR) distribution over an SFN area may facilitate the selection of transmission parameters according to the network topology. This paper presents a semianalytical method for the calculation of the SINR distribution in SFNs with low computational complexity compared to Monte Carlo simulations. The method, which builds on previous work developed for cellular communications, is applied to HPHT+LPLT SFNs and evaluated against different transmission and network parameters. [ABSTRACT FROM PUBLISHER]

Efficient and scalable media access control (MAC) protocol design is crucial to guarantee the reliable broadcast of safety messages in vehicular ad hoc networks. To devise a MAC for safety message broadcasting with reliability and minimum delay, in this paper, we propose a novel time slot-sharing MAC, referred to as SS-MAC, which can support diverse periodical broadcasting rates. In specific, we first introduce a circular recording queue to online perceive time slot occupying status. We then design a distributed time slot sharing (DTSS) algorithm and random index first fit (RIFF) algorithm, to efficiently share the time slot and make the online vehicle-slot matching, respectively. We prove theoretically the efficacy of DTSS algorithm, and evaluate the efficiency of RIFF algorithm by using MATLAB simulations. Finally, we conduct extensive simulations considering various driving scenarios and resource conditions to demonstrate the SS-MAC performance. [ABSTRACT FROM PUBLISHER]

The high speed, low cost, sharing of peripheral devices and central administration features of the Ethernet have led to it being widely trusted as the backbone for recent networks. However, it suffers from many practical limitations leading to a lack of scalability, owing to its broadcast and multicast mechanisms, particularly in relation to the discovery processes. Whilst software-defined networks (SDN) have overcome many legacy network problems, scalability remains a major issue, because broadcasting and multicasting have been inherited. Moreover, the problem is exacerbated with increasing network traffic, which results in higher bandwidth consumption, congestion, and increased probability of a single point of failure. To address this, servers under software-defined network architectures to eliminate discovery messages (SSED) is designed in this paper, and a backbone of floodless packets in an SDN LAN network is introduced. For SSED, flood discovery packets created by the dynamic host configuration protocol in the application layer and the address resolution protocol in the data link layer are considered, respectively. SSED eliminates any broadcast discovery packets with better performance, lowers peak overhead, and introduces an innovative mechanism for defining the relationship between the servers and SDN architecture. Experimental results after constructing and applying an authentic testbed verify that our proposed model has the ability to improve the scalability by removing broadcast packets from the data plane, reduction of control packets in the control plane, lessening peak overhead on the controller, preventing it experiencing failed requests, offering better response time, and providing more efficient performance. [ABSTRACT FROM AUTHOR]

This paper proposes a novel channel estimation technique for the offset quadrature amplitude modulation based filter bank multi-carrier (FBMC/OQAM) systems. Unlike the conventional approaches, the proposed pilot signals utilize their intrinsic interference for the channel estimation, and provide an improved power efficiency compared to the conventional auxiliary pilot method. However, due to the non-whiteness of the noise components at the output of the analysis filter banks, the power gain obtained by the proposed scheme cannot be maximized. To overcome this difficulty, we propose a semiblind channel estimation by grouping the pilot signals and imposing sign ambiguities to them. Theoretical analysis shows that the proposed semiblind channel estimation remarkably improves the power efficiency of its non-semiblind version. Finally, it is demonstrated that the near optimum detection performance is achieved by the proposed scheme at a reduced complexity. [ABSTRACT FROM PUBLISHER]

In the advanced television systems committee (ATSC) 3.0 system, the concept of flexibility is significant for supporting backward compatibility within the same ATSC 3.0 system. However, since the conventional bootstrap signal detection scheme is difficult to support the flexibility, the conventional bootstrap signal detection scheme should be newly designed according to the change of version. In this paper, a convolution neural network (CNN) model for bootstrap signal detection in ATSC 3.0 is proposed to maintain the flexibility of bootstrap. Additionally, for minimizing the loss of error performance of CNN-based bootstrap detection scheme, this paper proposes two dimensional alternate array to utilize the correlation of the adjacent bootstrap symbol and proposes the offline learning method using the bootstrap signal corrupted by noise to improve the error performance.

During the last two decades, terrestrial TV broadcasting has evolved from analog to digital technology, permitting a better spectrum efficiency, being more resistant to noise and interference as well as improving signal quality. High Definition TeleVison (HDTV) has been introduced to enhance the viewer's experience. HDTV and Ultra High Definition TeleVision bring the challenge of having a quasi-error free performance at a bit error rate as low as 10-12; i.e. less than one uncorrectable error during one hour's continuous transmission of 5 Mbps data stream. Such low error rates require robust standards, careful network planning and optimized service operation. Propagation phenomena have a direct (and possibly critical) impact on those three pillars. This paper fills the current gap of a thorough survey on propagation methods and models for broadcasting. We contribute to this field with a description and analysis of propagation phenomena concerning different aspects of the broadcast network planning, broadcast standard evaluation, and broadcast service operation. The paper provides also a technical perspective of state-of-the-art TV broadcast standards and discusses the relevancy of propagation studies with future and development and regulation challenges.

Transmission of high-definition (HD) video is a promising application for 60 GHz wireless links, since very high transmission rates (up to several Gbit/s) are possible. In particular we consider a sports stadium broadcasting system where signals from multiple cameras are transmitted to a central location. Due to the high pathloss of 60 GHz radiation over the large distances encountered in this scenario, the use of relays might be required. The current paper analyzes the joint selection of the routes (relays) and the compression rates from the various sources for maximization of the overall video quality. We consider three different scenarios: (i) each source transmits only to one relay and the relay can receive only one data stream, and (ii) each source can transmit only to a single relay, but relays can aggregate streams from different sources and forward to the destination, and (iii) the source can split its data stream into parallel streams, which can be transmitted via different relays to the destination. For each scenario, we derive the mathematical formulations of the optimization problem and re-formulate them as convex mixed-integer programming, which can guarantee optimal solutions. Extensive simulations demonstrate that high-quality transmission is possible for at least ten cameras over distances of 300 m. Furthermore, optimization of the video quality gives results that can significantly outperform algorithms that maximize data rates. [ABSTRACT FROM AUTHOR]

In this paper, we develop optimal power adaptation schemes by means of power amplification coefficients at the relay for half-duplex single-relay amplify-and-forward (AF) cooperative systems with channel side information (CSI) available at the relay. We consider both the orthogonal AF (OAF) and the nonorthogonal AF (NAF) transmission protocols. In particular, assuming that the relay has full knowledge of the channel gains, optimal power adaptation schemes under a long-term average power constraint are established in closed form using the mutual information (MI) and pairwise error probability (PEP) criteria with Gaussian inputs at the source. The proposed solutions can be understood as multidimensional (multi-D) distributed water filling in time and space. Numerical results show that the proposed power amplification methods provide a significant improvement over conventional schemes using either channel distribution information (CDI) or channel inversion (CI). The gain is observed with regard to the MI with Gaussian inputs and the bit-error-rate (BER) performance using finite constellations for both coded and uncoded systems. [ABSTRACT FROM AUTHOR]

A critical challenge for video-on-demand (VoD) services is to provide an entertainment service with minimum playback delay. A passive optical network (PON) that employs a high-speed optical fiber from an optical line terminal (OLT) to a number of optical network units (ONUs) can offer high bandwidth for multimedia applications (such as VoD services) in an access network. In this paper, we propose two novel video streaming techniques, called OLT broadcasting with ONU fast patching (BFP) and prediction-based OLT broadcasting and ONU fast patching (PBFP). The BFP scheme utilizes the ONU fast patching scheme at each ONU, and proposes a heuristic algorithm to find near optimum solutions of related optimization problem so that the worst-case playback delay (WPD) is minimized. The PBFP adds a prediction level for video popularity to the BFP scheme and uses a seamless channel transition technique to seamlessly change the number of channels allocated to videos. We study the efficiency of the proposed schemes when they are used in a shared wavelength division multiplexed passive optical network (Shared-WDM-PON) that adapts the broadcast nature of a GPON's downstream wavelength to WDM-PONs. Our simulation results indicate that the proposed schemes can improve both WPD and average playback delay performance parameters. [ABSTRACT FROM PUBLISHER]

This paper considers the precoder design for a bandwidth-efficient bit-interleaved coded modulation (BICM) system over nonorthogonal amplify-and-forward (NAF) single-relay channels with an arbitrary length of cooperative frame \2N. Based on the tight union bound to the bit error probability (BEP), we first derive an asymptotic design criterion with regard to a general \2N \times \2N rotation matrix. This expression allows us to develop a class of precoders that not only achieves full cooperative diversity but optimizes the asymptotic error performance as well. Interestingly, the developed class of optimal precoders indicates that the source should keep silent in the cooperative phase. In the broadcasting phase, it is shown that power is equally distributed to \2N information symbols at the source. By further examining the structure of the optimal class of \2N \times \2N precoders, it is then revealed that precoding over a group of at least two information symbols is sufficient to fully exploit diversity and coding advantages. Such a precoding technique, which is referred to as symbol grouping, therefore significantly reduces the system complexity without sacrificing the error performance. Among the pool of optimal precoders with respect to the asymptotic performance, the design of a precoder that provides a good convergence property is also discussed. Numerical examples show that the proposed precoder greatly improves the error performance of the cooperative system with low complexity. [ABSTRACT FROM PUBLISHER]

In this paper, we consider the issue of data broadcasting in mobile social networks (MSNets). The objective is to broadcast data from a superuser to other users in the network. There are two main challenges under this paradigm, namely 1) how to represent and characterize user mobility in realistic MSNets; 2) given the knowledge of regular users' movements, how to design an efficient superuser route to broadcast data actively. We first explore several realistic data sets to reveal both geographic and social regularities of human mobility, and further propose the concepts of geocommunity and geocentrality into MSNet analysis. Then, we employ a semi-Markov process to model user mobility based on the geocommunity structure of the network. Correspondingly, the geocentrality indicating the “dynamic user density” of each geocommunity can be derived from the semi-Markov model. Finally, considering the geocentrality information, we provide different route algorithms to cater to the superuser that wants to either minimize total duration or maximize dissemination ratio. To the best of our knowledge, this work is the first to study data broadcasting in a realistic MSNet setting. Extensive trace-driven simulations show that our approach consistently outperforms other existing superuser route design algorithms in terms of dissemination ratio and energy efficiency. [ABSTRACT FROM PUBLISHER]

A number of recent source coding techniques compress the source signal into multiple layers such that a destination is able to reconstruct the original signal (with some distortion) even if it has not received all the layers. Implementation of such source coding techniques in wireless networks requires the application of coding mechanisms (such as multilayer coding) which allow unequal error protection for different layers of the transmitted data. In this paper, we study the performance of multilayer coding for quasi-static fading channels where the source and the destination are equipped with multiple antennas and the Channel-State-Information (CSI) is only known at the destination. We limit the study to the scenarios where the destination is only able to perform successive-decoding (joint-decoding is not possible) and the objective is to find the design of a multilayer code which maximizes the average data rate received at the destination. To this end, we first propose a design rule for constructing a proper multilayer code for Multiple-Input-Multiple-Output (MIMO) networks. Furthermore, the paper presents a procedure which uses the proposed design rule to determine the parameters of the multilayer code. The performance of the designed multilayer coding scheme is then studied for different network setups. [ABSTRACT FROM AUTHOR]

Due to the recent proliferation of digital broadcasting, several methods for broadcast streaming data, i.e., movies or music, using the division-based broadcasting scheme have been studied. In the division-based broadcasting scheme, by dividing the data into several segments and broadcasting them via multiple channels, the waiting time for clients to start playing the data is reduced. These methods usually calculate appropriate channel bandwidths and allocate them to each channel. However, in many cases, channel bandwidths are fixed for the restrictions of the broadcasting system. Therefore, it is difficult to allocate arbitrary bandwidths to each channel. In this paper, we propose a division-based broadcasting method considering channel bandwidths. Our proposed method divides the data into several segments based on the given channel bandwidths. By dividing the data so that clients can receive the next segment immediately before finishing playing each segment, the waiting time is reduced satisfying the condition that clients can play the data without any interruptions. [ABSTRACT FROM PUBLISHER]

This paper describes the recent progress of research and development on transmission technologies for Super Hi-Vision (SHV), which is the form of ultrahigh-definition television (UHDTV) with the highest resolution class. The paper covers the transmission systems for SHV program production and satellite broadcasting. For short-haul transmission, an optical digital interface for video equipment was developed. It wavelength-multiplexes eight 10-Gb/s optical signals. It was experimentally confirmed that the transmission distance was at least 2 km, and that a series connection of the interfaces did not severely deteriorate jitter performance. We are also developing a 120-GHz-band wireless contribution short-haul link consisting of three transmitter/receiver pairs. All three pairs transmit and receive a 10.3-Gb/s signal at the same frequency. Experiments showed that transmission with little crosstalk is possible over a distance of 1.25 km when the receiver spacing is 8 m. A long-haul optical contribution link that we developed can transmit a 24-Gb/s SHV signal over a distance of 260 km by using optical amplifiers and no electronic repeaters. An IP network would be a good choice for long-distance links such as an international live contribution link. Several live IP transmissions of compressed video were conducted. Satellite relay transmission and broadcasting technology is also being developed. In particular, we have developed a QPSK/8PSK wide-band modem that uses LDPC and BCH codes. The modem could transmit 251-Mb/s (QPSK) and 677-Mb/s (8PSK) signals and was used in a live SHV satellite-transmission experiment. [ABSTRACT FROM PUBLISHER]

In this paper, we address the problem of estimating the maximal value over a sensor network using wireless links between them. We introduce two heuristic algorithms and analyze their theoretical performance. More precisely, i) we prove that their convergence time is finite with probability one, ii) we derive an upper-bound on their mean convergence time, and iii) we exhibit a bound on their convergence time dispersion. [ABSTRACT FROM PUBLISHER]

Localization is one of the most important issues in wireless sensor networks (WSNs). In the most widely proposed range-free algorithms, nodes estimate location by employing the geometric constraints imposed by the location of the mobile anchor. However, none of them addresses how the mobile anchor moves to optimize the improvement of location inaccuracies and minimize the anchor's movement. This paper assumes that previous range-free algorithms have been executed for a period of time and the deployed sensors are of different location inaccuracies. According to the size of the estimative region of each static sensor, an anchor-guiding mechanism is proposed to determine the beacon locations and construct an efficient path for the mobile anchor. Experimental study reveals that the proposed anchor-guiding mechanism effectively guides the mobile anchor to move along an efficient path, thereby saving the time required for improving or balancing the location inaccuracies of all sensor nodes. [ABSTRACT FROM PUBLISHER]

Bounding-box mechanism is a well-known low-cost localization approach for wireless sensor networks. However, the bounding-box location information cannot distinguish the relative locations of neighboring sensors, hence leading to a poor performance for some applications such as location-aware routing. This paper proposes a Differentiating Relative Locations (DRL) mechanism which uses a mobile anchor to broadcast tones and beacons aiming at distinguishing the relative locations of any two neighboring nodes. With the order of entering and leaving tone transmission range, each sensor is able to identify its relative location relation with each of its neighbors. In addition, two path planning mechanisms are proposed to guarantee that all sensors can identify their relative locations while the energy consumption of the mobile anchor can be effective. Theoretical analysis is developed to estimate the impacts of duty time of tone signals in terms of energy conservation and accuracy of relative locations. Experimental study reveals that the proposed mechanism effectively distinguishes relative locations of any two neighboring nodes and hence significantly improves the performance of location-aware routing in wireless sensor networks (WSNs). [ABSTRACT FROM PUBLISHER]

Heterogeneous quality-of-service (QoS) video broadcast over wireless network is a challenging problem, where the demand for better video quality needs to be reconciled with different display size, variable channel condition requirements. In this paper, we present a framework for broadcasting scalable video to heterogeneous QoS mobile users with diverse display devices and different channel conditions. The framework includes joint video source-channel coding and optimization. First, we model the problem of broadcasting a layered video to heterogeneous devices as an aggregate utility achieving problem. Second, based on scalable video coding, we introduce the temporal-spatial content distortion metric to build adaptive layer structure, so as to serve mobile users with heterogeneous QoS requirements. Third, joint Fountain coding protection is introduced so as to provide flexible and reliable video stream. Finally, we use dynamic programming approach to obtain optimal layer broadcasting policy, so as to achieve maximum broadcasting utility. The objective is to achieve maximum overall receiving quality of the heterogeneous QoS receivers. Experimental results demonstrate the effectiveness of the solution. [ABSTRACT FROM PUBLISHER]

Effective data broadcasting is essential in vehicular networks not only for road-safety message dissemination but also to aid routing and cooperative driving applications through periodic beaconing and to spread network initialization advertisements that are mandatory to support infotainment applications. Broadcast data are neither acknowledged nor retransmitted in case of failure, which raises the possibility of frame loss due to channel errors and collisions with multiple simultaneous broadcasts. This paper aims at modeling periodic broadcasting on the control channel of IEEE Std. 802.11p vehicular networks with multichannel architecture. Unlike previous related work, the proposed novel analytical approach accounts for mutual influence among nodes, frequent periodic updates of broadcasted data, standard network advertisement procedures, and 802.11p prioritized channel access with multichannel-related phenomena under various link quality conditions. [ABSTRACT FROM PUBLISHER]

The use of 3D models for progressive transmission and broadcasting applications is an interesting challenge due to the nature and complexity of such content. In this paper, a new image format for the representation of 3D progressive model is proposed. The powerful spectral analysis is combined with the state of art Geometry Image(GI) to encode static 3D models into spectral geometry images(SGI) for robust 3D shape representation. Based on the 3D model's surface characteristics, SGI separated the geometrical image into low and high frequency layers to achieve effective Level of Details(LOD) modeling. For SGI, the connectivity data of the model is implicitly encoded in the image, thus removing the need for additional channel bits allocated for its protection during transmission. We demonstrated that by coupling SGI together with an efficient channel allocation scheme, an image based method for 3D representation suitable for adoption in conventional broadcasting standard is proposed. The proposed framework is effective in ensuring the smooth degradation of progressive 3D models across varying channel bandwidths and packet loss conditions. [ABSTRACT FROM PUBLISHER]

This paper proposes a message partitioning-based distributed amplify-and-forward (MPDAF) cooperative scheme. In this scheme, the message transmitted by a user is partitioned into several equal parts, each of which will be relayed by a different user. It enables the cooperative users to share the relaying burden in a distributed network. As a result, each cooperative user deploys half of its transmission for broadcasting and the other half for relaying, maintaining both the degree of its broadcasting transmission and the spectral efficiency. Since cooperation does not require decoding and encoding processes at the relays, the system complexity of the MPDAF scheme is less than that of the space–time-coded (STC) distributed cooperative scheme, but some additional effort is required to achieve signal timing synchronization. Information theoretic analysis of the proposed scheme shows that it can achieve the same diversity–multiplexing tradeoff (DMT) performance bound as the STC scheme, achieving extra diversity gain without affecting its multiplexing gain. It is superior to the existing repetition-based distributed cooperative scheme. The scheme's outage performance substantiates this claim by showing that a significant diversity gain can be achieved. The impact of the MPDAF scheme when used in a practical coded system is analyzed, and it is shown that a diversity gain on the order of the number of relays can be achieved. We present simulation results for an MPDAF scheme employing the spectrally efficient bit-interleaved coded modulation and show that a significant diversity gain can be also achieved in a practical coded system. [ABSTRACT FROM PUBLISHER]

In this paper, we study two related iterative randomized algorithms for distributed computation of averages. The first algorithm is the Broadcast Gossip Algorithm, in which at each iteration one randomly selected node broadcasts its own state to its neighbors. The second algorithm is a novel variation of the former, in which at each iteration every node is allowed to broadcast: hence, this algorithm, which we call Collision Broadcast Gossip Algorithm (CBGA), is affected by interference among messages. The performance of both algorithms is evaluated in terms of rate of convergence and asymptotical error: focusing on large Abelian Cayley networks, we highlight the role of topology and of design parameters. We show that on fully connected graphs the rate of convergence is bounded away from one, whereas the asymptotical error is bounded away from zero. On the contrary, on sparse graphs the rate of convergence goes to one and the asymptotical error goes to zero, as the size of the network grows larger. Our results also show that the performance of the CBGA is close to the performance of the BGA: this indicates the robustness of broadcast gossip algorithms to interferences. [ABSTRACT FROM PUBLISHER]

Estimating 3D information from an image sequence has long been a challenging problem, especially for dynamic scenes. In this paper, a novel semi-automatic 2D-to-3D conversion method is presented to estimate the disparity maps for regular 2D video shots. Our method requires only a few user-scribbles on very sparse key frames, and then other frames of the video are converted to 3D automatically. Multiple objects are first segmented by the input user-scribbles. Then, the initial disparity map is assigned to each key frame with the aid of various preset disparity models for each object. After the disparity assignment step, disparity maps for other frames of the video are obtained through a disparity propagation strategy taking into account both color similarity and motion information. Finally, the 3D video is synthesized according to the type of 3D display device. Our method is verified on different kinds of challenging sequences containing occlusion, textureless regions, color ambiguity, large displacement movements, etc. The experimental results show that our method has better performance than the state-of-the-art 2D-to-3D conversion systems. [ABSTRACT FROM AUTHOR]

A main design issue in a wireless data broadcasting system is to choose between push-based and pull-based logic: The former is used as a low-cost solution, while the latter is preferred when performance is of utmost importance. Therefore, the most significant advantage of a push system is the minimal cost. This fact implies that hardware limitations do exist in the case of push systems. As a consequence, every related proposed algorithm should primarily be cost-effective. This attribute, however, has been overlooked in related research. In this paper, popular broadcast scheduling approaches are tested from an implementation cost aspect, and the results render them only conditionally realizable. Moreover, a new, cost-effective, adaptivity oriented schedule constructor is proposed as a realistic, minimal-cost solution. [ABSTRACT FROM PUBLISHER]

A number of commercial peer-to-peer (P2P) systems for live streaming have been introduced in recent years. The behavior of these popular systems has been extensively studied in several measurement papers. Due to the proprietary nature of these commercial systems, however, these studies have to rely on a “black-box” approach, where packet traces are collected from a single or a limited number of measurement points, to infer various properties of traffic on the control and data planes. Although such studies are useful to compare different systems from the end-user's perspective, it is difficult to intuitively understand the observed properties without fully reverse-engineering the underlying systems. In this paper, we describe the network architecture of Zattoo, one of the largest production live streaming providers in Europe at the time of writing, and present a large-scale measurement study of Zattoo using data collected by the provider. To highlight, we found that even when the Zattoo system was heavily loaded with as high as 20\,000 concurrent users on a single overlay, the median channel join delay remained less than 2–5 s, and that, for a majority of users, the streamed signal lags over-the-air broadcast signal by no more than 3 s. [ABSTRACT FROM PUBLISHER]