دانلود رایگان مقاله توزیع ویدئو کلان داده های مورد حمایت در ابر مخابراتی

Abstract

Telecom operators are starting the deployment of Content Delivery Networks (CDN) to better control and manage video contents injected into the network. Cache nodes placed close to end users can manage contents and adapt them to users’ devices, while reducing video traffic in the core. By adopting the standardized MPEG-DASH technique, video contents can be delivered over HTTP. Thus, HTTP servers can be used to serve contents, while packagers running as software can prepare live contents. This paves the way for virtualizing the CDN function. In this paper, a CDN manager is proposed to adapt the virtualized CDN function to current and future demand. A Big Data architecture, fulfilling the ETSI NFV guidelines, allows controlling virtualized components while collecting and pre-processing data. Optimization problems minimize CDN costs while ensuring the highest quality. Re-optimization is triggered based on threshold violations; data stream mining sketches transform collected into modeled data and statistical linear regression and machine learning techniques are proposed to produce estimation of future scenarios. Exhaustive simulation over a realistic scenario reveals remarkable costs reduction by dynamically reconfiguring the CDN.

6. Concluding remarks

A Big Data-backed virtualized CDN architecture to be deployed in the telecom cloud has been proposed in this paper. The tele- com CDN consists of a hierarchy of cache nodes: the centralized in- termediate cache nodes receive live-TV channels and prepare VoD contents, whereas the leaf cache nodes, located close to the end users, manage VoD contents access and adapt live-TV channels to users’ devices. Media content can be delivered over HTTP by using the stan- dardized MPEG-DASH technique and therefore, a virtualized leaf cache node would consist of a number of HTTP servers serving live 736 and stored contents to users. In addition, packagers are needed for live-TV preparation as well as a cache manager in charge of apply- ing caching policies to locally stored VoD contents. All these com- ponents can run as software inside VMs deployed in the same DC. A CDN manager is responsible for adapting the CDN function to current and future load. The CDN manager needs from an ar- 742 chitecture to control virtualized components and data collection and pre-processing functionalities; the proposed architecture fol- lows the ETSI NFV guidelines.