Linear Programming Models For Multi-Channel P2P Streaming Systems

Most of the commercial P2P video streaming deployments support hundreds of channels and are referred to as multichannel systems. Measurement studies show that bandwidth resources of different channels are highly unbalanced and thus recent research studies have proposed various protocols to improve the streaming qualities for all channels by enabling cross-channel cooperation among multiple channels. However, there is no general framework for comparing existing and potential designs for multi-channel P2P systems. The goal of this paper is to establish tractable models for answering the fundamental question in multi-channel system designs: Under what circumstances, should a particular design be used to achieve the desired streaming quality with the lowest implementation complexity? To achieve this goal, we first classify existing and potential designs into three categories, namely Naive Bandwidth allocation Approach (NBA), Passive Channel-aware bandwidth allocation Approach (PCA) and Active Channel-aware bandwidth allocation Approach (ACA). Then, we define the bandwidth satisfaction ratio as a performance metric to develop linear programming models for the three designs. The proposed models are independent of implementations and can be efficiently solved due to the linear property, which provides a way of numerically exploring the design space of multi-channel systems and developing closedform solutions for special systems

Strategies of collaboration in multi-channel P2P VoD streaming

As compared to live peer-to-peer (P2P) streaming, modern P2P video-on-demand (VoD) systems have brought much larger volumes of videos and more interactive controls to the Internet users. Nevertheless, the larger number of available videos and the flexibility of allowing users to jump back and forth in a video, have led to much fewer numbers of concurrent peers watching at a similar pace, that reduces the chance for collaborative chunk supply among peers and thus significantly increases the server bandwidth cost [1]. Towards the ultimate goal of maximizing peer resource utilization, in this paper, we design effective strategies for both cross-channel and intra-channel collaborations in multi-channel P2P VoD systems, such that individual peer's resources, including download/upload bandwidths and the cache capacity, are effectively utilized to maximize the streaming qualities in all the channels. In particular, each peer actively and strategically determines the supply-and-demand imbalance in different channels, as well as that among different chunks within each video, makes use of its surplus download capacity to fetch chunks with the most need, and then serves those chunks using its idle upload bandwidth, all without impairing its own streaming quality. Our extensive trace-driven simulations show the effectiveness of our strategies in reducing the server cost while guaranteeing high streaming qualities in the entire system, even during extreme scenarios such as unexpected flash crowds. ©2010 IEEE.published_or_final_versionThe IEEE Conference and Exhibition on Global Telecommunications (GLOBECOM 2010), Miami, FL., 6-10 December 2010. In Proceedings of GLOBECOM, 2010, p. 1-

Improving Streaming Capacity in Multi-Channel P2P VoD Systems via Intra-Channel and Cross-Channel Resource Allocation

Multi-channel Peer-to-Peer (P2P) Video-on-Demand (VoD) systems can be categorized into independent-channel P2P VoD systems and correlated-channel P2P VoD systems. Streaming capacity for a channel is defined as the maximal streaming rate that can be received by every user of the channel. In this paper, we study the streaming capacity problem in multi-channel P2P VoD systems. In an independent-channel P2P VoD system, there is no resource correlation among channels. Therefore, we can find the average streaming capacity for the independent-channel P2P VoD system by finding the streaming capacity for each individual channel, respectively. We propose a distributed algorithm to solve the streaming capacity problem for a single channel in an independent-channel P2P VoD system. The average streaming capacity for a correlated-channel P2P VoD system depends on both the intra-channel and cross-channel resource allocation. To better utilize the cross-channel resources, we first optimize the server upload allocation among channels to maximize the average streaming capacity and then propose cross-channel helpers to enable cross-channel sharing of peer upload bandwidths. We demonstrate in the simulations that the correlated-channel P2P VoD systems with both intra-channel and cross-channel resource allocation can obtain a higher average streaming capacity compared to the independent-channel P2P VoD systems with only intra-channel resource allocation