SELECTIVELY CACHING VIDEO TO IMPROVE ON-DEMAND RESPONSE TIME

摘要

A technique for delivering on-demand broadcast program or other multimedia content by the selective deployment of specialized cache servers close to the subscriber side viewing device which accumulates data that represents on-demand material. A packet redirector within the cache server allows program content in the form of data packets to either be routed to the cache server for storage or straight through the redirector to the viewing device. The redirector thus permits previously cached packets to be inserted in line with content presently being delivered on the fly to the video server. In addition, a network level cache may be employed at a head end to locally cache all, or a portion of, particularly popular content. This allows the head end cache to offload broadcast multimedia server from certain responsibilities associated with on-demand delivery. As a result, the demand portion of the system is placed under control of the subscriber side thereby freeing the head end from the complexities of having to deliver content on demand, or to insert material specific to particular subscribers such as advertisements.