Video Contents Prior Storing Server for Optical Access Network

Multimedia Tools and Applications, 2006

This paper proposes a new video distribution service: Video-In-Network (VIN). In VIN, videos are continuously circulating in an optical network where they can be easily retrieved by VIN Nodes. A mathematical model of the VIN system was derived and used to explore the performance of VIN in terms of the maximum number of concurrent video streams which can be supported by the system. We then compared VIN with Staggered Multicast. We found that VIN has a number of advantages over Staggered Multicast. First, VIN is more scalable in terms of the number of streams/channels. Second, the startup latency of VIN is shorter than that of Staggered Multicast. Third, Staggered Multicast is a near-VOD system and the video clients usually have no specific channels to the server to request for video. In the VIN system, the video clients can request the VIN Node for particular videos for multicast or unicast on demand.

Delayed-Multicast is a novel transmission technique to support Video-on-Demand. It introduces buffers within the network to bridge the temporal delays between similar requests thus minimizing the aggregate bandwidth and server load. This paper introduces an improved online algorithm for resource allocation with Delayed-Multicast by utilizing prior knowledge of each clip's popularity. The algorithm is intended to be simple so as to allow for deployment at multiple levels in a distribution network. The result is greater backbone traffic savings and a corresponding reduction in the server load.

IEEE/AFCEA EUROCOMM 2000. Information Systems for Enhanced Public Safety and Security (Cat. No.00EX405), 2000

In typical proposals for Video-on-demand (VOD) networks, customers are serviced individually by allocating and dedicating a transmission channel and a set of service sources to each customer. In this paper an interactive VOD optical network is proposed that can offer video, TV, banking and shopping services (among others) to a large number of users. Several network parameters are studied using computer simulation taking into account effects like fiber dispersion, node distance and network usage. The studied parameters include maximum overall fiber transmission rate, average user waiting time, and fiber percentage usage time.

IEEE Consumer Electronics Magazine, 2019

IEEE Transactions on Circuits and Systems for Video Technology, 2013

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. Index Terms-Broadcasting, multicasting, passive optical network (PON), patching, video-on-demand (VoD). Nomenclature D i Duration of watching video i from 1 to L i in minutes e The number of unassigned patching channels G l The group of segments from S 1 to S l i The counter of video titles id ij The interest degree of video i at ONU j j The counter of ONUs k The number of video segments L i The length of video i in minutes l The counter of patching channels M Total number of video titles in video server N Total number of ONUs

2000

Despite advances in networking technology, the limitation of the server bandwidth prevents multimedia applications from taking full advantage of next-generation networks. This constraint sets a hard limit on the number of users the server is able to support simultaneously. To address this bottleneck, we propose a Caching Multicast Protocol (CMP) to leverage the in-network bandwidth. Our solution caches video streams in the routers to facilitate services in the immediate future. In other words, the network storage is managed as a huge \video server" to allow the application to scale far beyond the physical limitation of its video server. The tremendous increase in the service bandwidth also enables the system to provide true on-demand services. To assess the e ectiveness of this technique, we d e v elop a detailed simulator to compare its performance with that of our earlier scheme called Chaining. The simulation results indicate that CMP is substantially better with many desirable properties as follows: it is optimized to reduce tra c congestion (2) it uses much less caching space (3) client w orkstations are not involved in the caching protocol (4) it can work on the network layer to leverage modern routers.

2001

In this paper, we study how to distribute cache sizes into a tree structured server for transmitting video streams through videoon-demand (VoD) way. We use off-line smoothing for videos and our request rates are distributed according to a 24 hour audience curve. For this purpose we have designed a slotted-time bandwidth reservation algorithm, which has been used to simulate our experiments. Our system tests the quality of service (QoS) in terms of starting delay, and once a transmission has started, the system guarantees that it will be transmitted without any delay or quality loss. We tested it for a wide range of users (from 800 to 240 000) and also for a different number of available videos. We demonstrate that a tree structured system with uniform cache sizes performs better than the equivalent system with a proxy-like configuration. We also study delay distribution and bandwidth usage in our system on a representative case.

IEEE Transactions on Circuits and Systems for Video Technology, 2001

A closed-loop (demand-driven) approach toward video-on-demand services, called multicast cache (Mcache), is discussed in this paper. Servers use multicast to reduce their bandwidth usage by allowing multiple requests to be served with a single data stream. However, this requires clients to delay receiving the movie until the multicast starts. Using regional cache servers deployed over many strategic locations, Mcache can remove the initial playout delays of clients in multicast-based video streaming. While requests are batched together for a multicast, clients can receive the prefix of a requested movie clip from caches located in their own regions. The multicast containing the later portion of the movie can wait until the prefix is played out. While this use of regional caches has been proposed previously, the novelty of our scheme lies in that the requests coming after the multicast starts can still be batched together to be served by multicast patches without any playout delays. The use of patches was proposed before, but they are used either with unicast or with playout delays. Mcache effectively hires the idea of a multicast patch with caches to provide a truly adaptive video-on-demand service whose bandwidth usage is up to par with the best known open-loop schemes under high request rates while using only minimal bandwidth under low request rates. In addition, efficient use of multicast and caches removes the need for a priori knowledge of client disk storage requirements which some of the existing schemes assume. This makes Mcache ideal for the current heterogeneous Internet environments where those parameters are hard to predict. We further propose the Segmented Mcache (SMcache) scheme which is a generalized and improved version of Mcache where the clip is partitioned into several segments in order to preserve the advantages of the original Mcache scheme with nearly the same server bandwidth requirement as the open loop schemes under high request rates. I. INTRODUCTION V IDEO-ON-DEMAND (VoD) is gaining popularity in recent years with the proliferation of high bandwidth networks. Applications using VoD include news distribution (for example, headline news from cnn.com), distance learning and entertainment video distribution. Deployment of new technologies in last mile access networks such as DSL and cable modem have made VoD over the Internet possible. A typical VoD system consists of a set of centralized video servers and geographically distributed clients connected through high-speed networks. A large number of video files are Manuscript

Telsys, 1998

Providing cost-e ective video-on-demand (VOD) services necessitates reducing the required bandwidth for transporting video over high-speed networks. In this paper, we investigate e cient schemes for transporting archived MPEG-coded video over a VOD distribution network. A video stream is characterized by a time-varying tra c envelope, which provides an upper bound on the bit rate. Using such envelopes, we show that video streams can be scheduled for transmission over the network such that the per-stream allocated bandwidth is signi cantly less than the source peak rate. In a previous work 13], we investigated stream scheduling and bandwidth allocation using global tra c envelopes and homogeneous streams. In this paper, we generalize the scheduling scheme in 13] to include the heterogeneous case. We then investigate the allocation problem under window-based tra c envelopes, which provide tight bounds on the bit rate. Using such envelopes, we introduce three stream-scheduling schemes for multiplexing video connections at a server. The performance of these schemes is evaluated under static and dynamic scenarios. Our results indicate a signi cant reduction in the per-stream allocated bandwidth when stream scheduling is used. While this reduction is obtained through statistical multiplexing, the transported streams are guaranteed stringent, deterministic quality of service (i.e., zero loss rate and small, bounded delay). In contrast to video smoothing, our approach require virtually no bu er at the set-top box since frames are delivered at their playback rate.

Transmission of variable-bit-rate (VBR) video over packet- switched networks is a very challenging problem, and has received much attention in the research community. The burstiness of VBR video makes it very hard to design efficient transmission schemes that will achieve a high level of network utilization. Promising work has been done recently for the transmission of stored video, based on the idea of video prefetching. These protocols use a buffer located at the client's set-top box (STB) to store future frames that are sent when the transmission link is underutilized. Experi- mental results have shown that video prefetching can achieve a utilization of almost 100% without any need for buffering inside the network. How- ever, no admission control algorithm has been proposed for these protocols to enable their deployment. In this paper, we use the theory of effective bandwidths to develop an admission control algorithm. Each user is al- lowed to interact with the system, and ...