The Research On IPTV Service Carrying Network

China Netcom Corporation(CNC)have begun its exploration on IPTV and related techniques from 2005 the March.Given such a huge IP network as Beijing local IP network,considered the trends of network convergence,we have drawn an explicit conclusion that operate the new IPTV service on the same network.To solve the three main problems which are multicast protocol choosing,multicast distribution point choosing and user address & AAA,CNC Beijing branch organized a series of discussion on multicast based on the basic requirement of IPTV service.Using global leading carrier's experience for reference,we make some new development to the application of multicast considered the instance of Beijing local IP network.Soon the initial network topology of carrying IPTV service using both multicast and unicast techniques was brought out in the first time.After that,the Internet management center of CNC Beijing branch did the multicast tests with all the equipment manufaturer in the scheme discussion stage,in order to verify the feasibility of the several may-be topologies.According to the former technical discussion,test results,network conception and service type,user scale estimated by market department,drew a more integrated IPTV network plan by the first time.Finally we release a blue print of deploy PIM-SM as multicast protocol,DSLAM as multicast distribution point,using private address without AAA.And do further necessary exploration on future network technology.In the implementation stage,after the consultation with market department and other technical support department,we've chosen forty service areas to be the final ones to deploy IPTV services according to user scale and ADSL lines quality.Together we'll be dedicated to make Beijing local IP network the first commercial multicast media carrying network.In the Beijing local IP Network,the number of routers deployed multicast feature has exceed one hundred by now.The router types cover the super core routers,the core routers and the SR-7750 which sited in access layer.The equipment manufacturers related cover Cisco,Huawei technology and Shanghai Bell Alcatel,with the router types of Cisco 120xx series\128xx series\Huawei NE5000E\NE80E\ASB SR-7750.Besides the discussion on IPTV service integrated solution,this paper will specially concentrate on IP core network carrying technology of IPTV.