Multi-rate control method using layered content

Layered multicasting based on layer-coded content has been proposed to deliver streaming video contents at multiple rates to users on access lines with various bandwidths, such as ADSL, FTTH, and wireless LAN. We propose an IP multicasting rate control system using layered content, called multirate filtering (MRF), to optimize the streaming rate by controlling the number of content layers for each VLAN when a shared line of an edge node is congested. MRF can allocate the bandwidth of the shared line to VLANs according to their utilizations and then transmit a multicast content to clients with different stream rates reflecting the users´ intentions. We demonstrate experimentally that the quality of video transmitted by applying MRF in a real network is superior to that transmitted by the conventional priority queuing control scheme under congestion. We also show that MRF can control the content rate according to a user´s receiving priority when viewing two or more contents. Our results further demonstrate that MRF can coexist with another application by sharing bandwidth.