Providing On - Demand Video Services Using Request

| In an on-demand video system, requests for a video le arriving within a period of time can be batched together and served with a single multicast stream; thereby reducing the bandwidth requirement compared with the un-batched case. In this paper, we study various batching schemes to meet delay and prootability requirements | in the window-size based and moving-average schemes, maximum and average user delay respectively are guaranteed; in the batch-size based scheme, minimal prootability is maintained; in the adaptive scheme, both the delay and prootability can be balanced. We analyse and compare these schemes in terms of the delay experienced by the users, and their prootability (the number of users in a batch, the number of concurrent streams, etc.).