Harmonic Broadcasting Scheme Research Articles

Wrap Harmonic Broadcasting and Receiving Scheme for Popular Video Service

Broadcasting has been proved to be an efficacious approach of video-on-demand (VOD) service. Over the past few decades, many scholars have devoted a great deal of time to the study of broadcasting. Among all available schemes, harmonic broadcasting (HB) scheme points out the minimum bandwidth required to broadcast a popular video given a fixed viewers’ waiting time. HB divides each segment equally into several horizontal subsegments in line with the harmonic series. However, such segmentation is too complex to be feasible. To solve this problem, we come up with an original scheme dubbed wrap HB (WHB), in which we partition each segment equally into vertical subsegments according to its serial number. Given a fixed channel allocation, the maximum number of segments of our scheme approaches to the theoretical upper bound. Compared to the fast broadcasting scheme and the recursive frequency-splitting scheme, the buffer requirement in the WHB scheme decreases by 26%. We also design a simple VBR WHB (SVWHB) scheme to accommodate VBR video based on the WHB scheme. The comprehensive simulation results indicate that the SVWHB scheme has similar savings as the WHB scheme.

An adaptive harmonic broadcasting scheme with download and playback synchronisation for video on demand

Harmonic broadcasting is a broadcasting scheme to reduce the bandwidth requirement in video-on-demand service where a video is divided into segments of equal size and each segment is repeatedly transmitted over a number of channels having bandwidth that follows a harmonic series. As the bandwidth of channels differ from each other and a user can join at any time to these multicast channels, a synchronisation problem between download and playback is created. To deal with this issue, some schemes have been proposed, however, at the cost of additional or wastage of bandwidth. In this paper, we propose an adaptive harmonic broadcasting scheme that deals with the synchronisation problem at the same average bandwidth consumption as traditional harmonic broadcasting scheme. We present several analytical results to exhibit the efficiency of the proposed scheme over the existing ones.

A Hybrid Video-on-Demand Data Broadcasting and Receiving Scheme of Harmonic and Staggered Schemes

In providing video-on-demand (VoD) services to a number of clients through networks, the bandwidth requirements of video transmission restrict VoD services. For this reason, many significant broadcasting-based VoD schemes have been proposed to efficiently support services. However, the broadcasting-based VoD schemes approach needs frequency channel hopping, using many channels at the same time and managing many segments of a video. These make it difficult to implement. In this paper, we propose a harmonic staggered broadcasting scheme which has a simple structure and substantially improved VoD efficiency. The proposed scheme substantially reduces the number of segments required and the frequency for switching channels. Also this new scheme performs significantly better than the existing VoD schemes in viewer's waiting time and buffer requirements with simplicity. The numerical results demonstrate that the viewer's waiting time of the harmonic staggered broadcasting scheme is close to the harmonic broadcasting scheme and the buffer requirements of this can be adjusted by a video dividing coefficient <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">h</i> .

Geometrico-Harmonic Broadcasting Scheme With Continuous Redundancy

The harmonic broadcasting scheme has the best performance for the user latency. It, however, does not always provide the video data in time to the users. To provide the video data reliably, its two main variants - cautious and quasi-harmonic schemes have been proposed. They require more bandwidth than the harmonic scheme. The cautious and quasi-harmonic schemes need 0.50 b and 0.1771 b more bandwidth, respectively, than the harmonic scheme in limiting case. In this paper, a new broadcasting scheme: geometrico-harmonic scheme with continuous redundancy is proposed. This scheme provides the video data in time unlike the harmonic scheme, and its bandwidth requirement can be had as close to that of the harmonic scheme as we please. Moreover, the extra bandwidth required in this scheme can be evaluated at any point of time, that is, it can be estimated for a fractional size of a segment and/or subsegment. The bandwidth is a scarce resource and its requirement for any fractional size of segments (or subsegments) may be helpful while dealing with the variable bandwidth rate-encoded videos. In the proposed scheme, the user latency can be made arbitrarily close to that of the harmonic scheme. In comparison to the cautious and the quasi-harmonic schemes, it has better performance for the user latency as well as the buffer storage. For disk transfer rate, it performs better than the quasi-harmonic scheme and in comparison to the cautious harmonic scheme its performance is same

Multiplexed harmonic broadcasting scheme for efficient video-on-demand services

Periodic broadcasting schemes can improve the efficiency of video-on-demand (VOD) services by reducing the bandwidth requirement to transmit popular videos. The harmonic broadcasting scheme has the best performance in reducing service bandwidth under a given access time, but it uses too many channels. However, a multiplexed harmonic broadcasting scheme that overcomes this drawback is now proposed. This scheme divides each video into equal-sized segments and then broadcasts segments periodically in a small number of sever channels with equal bandwidth. The idea of segment-to-channel mapping in the scheme is inspired by the time division multiplexing system. Each segment is divided equally into several subsegments; subsegments of different segments are multiplexed in a slot with the guarantee of being able to keep playing out continuously for every user. The proposed scheme outperforms the pagoda broadcasting and recursive frequency splitting schemes in reducing the viewers' maximum waiting time, and the scheme requires less client storage.

The enhanced staircase broadcasting for VBR videos

One way to broadcast a popular video is to partition the video into segments, which are broadcasted on several streams periodically. The approach lets multiple users share streams; thus, the stress on the scarce bandwidth can be alleviated without sacrificing viewers' waiting time. One representative approach is the Staircase Broadcasting (SB) scheme, which requires buffering only 25% of a playing video. However, the scheme mainly supports transmission of CBR-encoded videos. In this paper, we proposed a simple VBR staircase broadcasting (SVSB) scheme, which can distribute VBR-encoded videos with small buffers. The idea behind the scheme is asynchronous downloading and playing, and hybrid division by length and size. It is simple and effective. We also applied the design to several segmented broadcasting schemes, such as the harmonic-based broadcasting, and the recursive frequency-splitting (RFS) schemes, to enable them to support VBR videos. A simulation was conducted to evaluate the schemes. The results indicated that the SVSB scheme still outperforms on required buffers, and disk transfer rate at client end. The harmonic broadcasting scheme with VBR support consumes the least bandwidth.

Modified staircase data broadcasting scheme for popular videos

In a broadcasting scheme, the user's latency is a very important parameter. The harmonic broadcasting scheme has been found to have the best performance for user's latency and staircase broadcasting scheme has been found to have the best performance for local storage as well as for disk transfer rates. In this paper a modified staircase scheme has been proposed which shows that if the video data is downloaded with lesser speed which would save the local storage and hence the disk transfer rate, the users still can be provided with the video in a continuous manner without any jerk or jitter. Further, if the downloading rate of the video is reduced after 3.25 channels, the users' services for viewing the videos does not get affected. In particular, for employing bandwidth of about 40 mbps, the modified staircase data scheme shows the performance for user latency about 29% better and the local storage is same but disk I/O transfer rates are slightly higher (4%) in comparison to staircase scheme. In comparison to harmonic scheme, user's latency is 24% higher but buffer storage and disk I/O transfer rates are about 35% and 30%, respectively, better for the same bandwidth. However the values of the performance parameters converge to those of harmonic scheme as the bandwidth is increased.

On optimal broadcasting scheme for popular video service

In order to approach a video-on-demand (VOD) service, we can allocate more bandwidth to broadcast a popular video more frequently to reduce viewers' waiting time. Using a broadcasting scheme to support a popular video periodically, in order to guarantee a given waiting time, the harmonic broadcasting scheme needs the least bandwidth in the existing schemes. In this paper, we show that using any broadcasting scheme, the minimum bandwidth requirement for the same waiting time is the same as the harmonic broadcasting scheme. Therefore, for a popular video, in order to approach a near VOD service, the harmonic broadcasting scheme is an optimal broadcasting scheme that needs the least bandwidth for a given viewers' waiting time.

Enhanced harmonic data broadcasting and receiving scheme for popular video service

For a popular movie, in order to minimize the service delay with a given bandwidth, currently the harmonic broadcasting scheme can provide users with the shortest waiting time to approach near video-on-demand service. This paper presents an enhanced scheme, which can improve the bandwidth utilization and reduce further the viewers' waiting time.

Fast data broadcasting and receiving scheme for popular video service

Using multiple channels to broadcast a popular video can reduce the viewer's waiting time to approach video-on-demand service. For a given bandwidth allocation, pyramid broadcasting schemes can provide users with shorter waiting time as compared with conventional broadcasting schemes. However, for a 120-minute movie, the waiting time is only reduced to 20 minutes as we allocate 4 video channels for the movie. The harmonic broadcasting scheme can reduce the waiting time to 4 minutes but it can not support the live telecast. This paper presents a new broadcasting scheme, which can support live videos and reduce the waiting time to 8 minutes for the above case. With the same waiting requirement for a hot video, the new scheme can greatly reduce the bandwidth requirements and provide heterogeneous users' services.