Analysis of a CDN–P2P hybrid architecture for cost-effective streaming media distribution

Abstract

To distribute video and audio data in real-time streaming mode, two different technologies -Content Distribution Network (CDN) and Peer-to-Peer (P2P) -have been proposed. However, both technologies have their own limitations: CDN servers are expensive to deploy and maintain, and consequently incur a cost for media providers and/or clients for server capacity reservation. On the other hand, a P2P-based architecture requires sufficient number of seed supplying peers to jumpstart the distribution process. Compared with a CDN server, a peer usually offers much lower out-bound streaming rate and hence multiple peers must jointly stream a media data to a requesting peer. Furthermore, it is not clear how to determine how much a peer should contribute back to the system after receiving the media data, in order to sustain the overall media distribution capacity.In this paper, we propose and analyze a novel hybrid architecture that integrates both CDN-and P2P-based streaming media distribution. The architecture is highly costeffective: it significantly lowers the cost of CDN capacity reservation, without compromising the media quality delivered. In particular, we propose and compare different limited contribution policies for peers that request a media data, so that the streaming capacity of each peer can be exploited on a fair and limited basis. We present: (1)

Efficient Placement Schemes to Fully Utilize Peer Upstream Bandwidth

“…Different from the approaches [4]- [10], we focus on efficient schemes for minimizing server load and ensuring streaming quality in a two-level hybrid architecture. In tbis paper, we use a hybrid streaming atchitecture tbat integrates CDN and P2P networks [5][10], as shown in Figure 3.…”

“…For example, in Coopnet [7], the system uses a centralized tree management algorithm to construct and maintain a diverse set of delivery paths. Many incentive contnbution polices [10][28] [29] are also proposed to encourage peers to commit their recourses. For example, [29] proposed applying the social taxation model to peer contribution: the amount of recourse that a peer is required to contnbute is based on the quality of the service that a peer receives.…”

Policy-driven multi-file distribution

“…The distribution of high-volume data poses new challenges and has led to cost-effective file distribution techniques. We have shown in [1] that the P2P (Peer-to-Peer) architecture, if properly jumpstarted by the CDN (Content Distribution Network) capacity, can dynamically generate and maintain aggregated file distribution capacity that satisfies subsequent file requests with low request rejection rate. In P2P data distribution, an individual peer offers limited storage space and out-bound data rate.…”

“…Our peer contribution policy in [1] is based on the volume of the file that is being distributed. Each peer is requested to transmit a total amount of data equal to r (r ≥ 1) times the file size, regardless of the out-bound data rate it commits.…”

“…An analysis is presented to capture the relation between the overall file distribution capacity and the individual peer contribution, demonstrating the impact of the latter on the former. However, the analysis in [1] assumes that the peer contribution policy is file-specific. In other words, after a peer receives a specific file f , it will fulfill its contribution commitment by re-distributing only the content of file f .…”