The Design And Application Of CDN Technology In The Broadcasting And TV VOD Platform

With the continuous change in Internet technology and the convergence of the three networks intensified,it brings new challenges to traditional broadcasting and television operators.Through the network construction and network bidirectional transformation,radio and television network provides the possibility of VOD platform construction.Since Comcast Corporation of the United States proposed the Next Generation On Demand(NGOD),more and more radio and television operators view it as the standard video architecture.The interactive platform under NGOD adopts standard interfaces and protocols and opens the interface between modules,which makes the structure of the platform more reasonable.The NGOD architecture is valuable in use.More cable operators in China use the NGOD as the framework to develop the VOD platform.The Content Delivery Network(CDN)distributes the content resources to the “edge” of the network closest to the user by adding a new layer of network architecture to the existing network,so that users can obtain the desired content at hand.It is close to the network congestion situation and improves the quality of service for users to obtain services.First of all,this paper analyzes the basic structure system,network architecture,key technologies of the current content distribution system and the advantages in terms of scalability and service quality.Secondly,according to the actual operation of the broadcasting and television network,the two major architectures(ISA and NGOD)are analyzed.The differences and advantages of the two major architectures are compared and analyzed.The better applicable NGOD architecture as the technical standard for the VOD platform of the City Cable TV is chose.In order to provide better services for users,the VOD platform is guaranteed to provide video services in a stable and efficient manner and introduce a CDN system.Finally,according to the NGOD standard system and the technical specifications of the Province two-way on-demand system,the interface functions and protocolparameters of the CDN system are designed.The City cable frequency is divided according to the DVB-C standard.According to the characteristics of the cable TV network,IPQAM is deployed in the front-end equipment room to fully utilize the downlink bandwidth resources of the wired network to ensure smooth video playback without jamming.