scholarly journals LIVE STREAMING USING PEER DIVISION MULTIPLEXING

Author(s):  
ABHISHEK.V. RAO ◽  
MANIKANDAN. A ◽  
AZARUDEEN. A ◽  
DEVENDAR RAO

A Number of commercial peer-to-peer (P2P) systems for live streaming have been introduced in recent years. The behaviour of the popular systems has been extensively studied in several measurement papers. 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 the traffic on the control and data planes. Although, such studies are useful to compared different systems from the end user’s perspective. It is difficult to intuitively understand the observed properties without fully reverseengineering 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 20000 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 more than 3 s.

Author(s):  
Lu Liu ◽  
Duncan Russell ◽  
Jie Xu

Peer-to-peer (P2P) networks attract attentions worldwide with their great success in file sharing networks (e.g., Napster, Gnutella, BitTorrent, and Kazaa). In the last decade, numerous studies have been devoted to the problem of resource discovery in P2P networks. Recent research on structured and unstructured P2P systems provides a series of useful solutions to improve the scalability and performance of service discovery in large-scale service-based systems. In this chapter, the authors systematically review recent research studies on P2P search techniques and explore the potential roles and influence of P2P networking in dependable service-based military systems.


2007 ◽  
Vol 2007 ◽  
pp. 1-9 ◽  
Author(s):  
Mo Zhou ◽  
Yafei Dai ◽  
Xiaoming Li

The architecture of P2P file-sharing applications has been developing to meet the needs of large scale demands. The structured overlay network, also known as DHT, has been used in these applications to improve the scalability, and robustness of the system, and to make it free from single-point failure. We believe that the measurement study of the overlay network used in the real file-sharing P2P systems can provide guidance for the designing of such systems, and improve the performance of the system. In this paper, we perform the measurement in two different aspects. First, a modified client is designed to provide view to the overlay network from a single-user vision. Second, the instances of crawler programs deployed in many nodes managed to crawl the user information of the overlay network as much as possible. We also find a vulnerability in the overlay network, combined with the character of the DNS service, a more serious DDoS attack can be launched.


2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Laizhong Cui ◽  
Nan Lu ◽  
Fu Chen

Most large-scale peer-to-peer (P2P) live streaming systems use mesh to organize peers and leverage pull scheduling to transmit packets for providing robustness in dynamic environment. The pull scheduling brings large packet delay. Network coding makes the push scheduling feasible in mesh P2P live streaming and improves the efficiency. However, it may also introduce some extra delays and coding computational overhead. To improve the packet delay, streaming quality, and coding overhead, in this paper are as follows. we propose a QoS driven push scheduling approach. The main contributions of this paper are: (i) We introduce a new network coding method to increase the content diversity and reduce the complexity of scheduling; (ii) we formulate the push scheduling as an optimization problem and transform it to a min-cost flow problem for solving it in polynomial time; (iii) we propose a push scheduling algorithm to reduce the coding overhead and do extensive experiments to validate the effectiveness of our approach. Compared with previous approaches, the simulation results demonstrate thatpacket delay,continuity index,andcoding ratioof our system can be significantly improved, especially in dynamic environments.


Author(s):  
K. suguna ◽  
K. Madhavi

Many two-layer hierarchy unstructured peer-to-peer (P2P) systems, comprising of superpeers and ordinary peers improved the performance of large scale P2P systems. The construction and maintenance of the superpeer overlay network play an important role in improving the performance P2P systems. One efficient method of constructing the superpeer overlay network is based on notion of Perfect Difference Networks(PDN).The construction and maintenance of network in this method is controlled by single bootstrap server. Such network is prone to single-point failures. The number of registration requests lost before getting up the failed bootstrap server and the delay in adding new peer to the network gets increased. The mechanism of maintaining and constructing the superpeer overlay network by making use of two bootstrap servers having slight different functionality proposed in this paper avoids single-point failures. It also ensures no loss of registration requests. The experimental results show that the delay in adding new peer to the network and number of registration requests lost are reduced.


Author(s):  
Haiying Shen

Structured peer-to-peer (P2P) overlay networks like Distributed Hash Tables (DHTs) map data items to the network based on a consistent hashing function. Such mapping for data distribution has an inherent load balance problem. Thus, a load balancing mechanism is an indispensable part of a structured P2P overlay network for high performance. The rapid development of P2P systems has posed challenges in load balancing due to their features characterized by large scale, heterogeneity, dynamism, and proximity. An efficient load balancing method should flexible and resilient enough to deal with these characteristics. This chapter will first introduce the P2P systems and the load balancing in P2P systems. It then introduces the current technologies for load balancing in P2P systems, and provides a case study of a dynamism-resilient and proximity-aware load balancing mechanism. Finally, it indicates the future and emerging trends of load balancing, and concludes the chapter.


2020 ◽  
Vol 2020 (10) ◽  
pp. 181-1-181-7
Author(s):  
Takahiro Kudo ◽  
Takanori Fujisawa ◽  
Takuro Yamaguchi ◽  
Masaaki Ikehara

Image deconvolution has been an important issue recently. It has two kinds of approaches: non-blind and blind. Non-blind deconvolution is a classic problem of image deblurring, which assumes that the PSF is known and does not change universally in space. Recently, Convolutional Neural Network (CNN) has been used for non-blind deconvolution. Though CNNs can deal with complex changes for unknown images, some CNN-based conventional methods can only handle small PSFs and does not consider the use of large PSFs in the real world. In this paper we propose a non-blind deconvolution framework based on a CNN that can remove large scale ringing in a deblurred image. Our method has three key points. The first is that our network architecture is able to preserve both large and small features in the image. The second is that the training dataset is created to preserve the details. The third is that we extend the images to minimize the effects of large ringing on the image borders. In our experiments, we used three kinds of large PSFs and were able to observe high-precision results from our method both quantitatively and qualitatively.


NASPA Journal ◽  
1998 ◽  
Vol 35 (4) ◽  
Author(s):  
Jackie Clark ◽  
Joan Hirt

The creation of small communities has been proposed as a way of enhancing the educational experience of students at large institutions. Using data from a survey of students living in large and small residences at a public research university, this study does not support the common assumption that small-scale social environments are more conducive to positive community life than large-scale social environments.


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