Some type of transmission rate control protocol is required in order to support multicast video applications over the Internet. Previously, researchers have proposed two basic families of control protocols. The first, sender based rate-adaptation, focuses on the sender. The sender uses a single channel to transmit the video signal to all receivers, and the sender adjusts the transmission rate of this single channel based upon network or receiver feedback. The second protocol focuses on the receivers. The sender stripes the video signal across multiple multicast channels, and each receiver selectively adds and drops channels to meet their individual needs. We propose a new protocol Layered Multicast Control Protocol (LMCP), which melds the strengths of the two previous approaches. The sender stripes the video signal across multiple multicast channels, and each receiver selectively adds and drops channels to meet their individual needs. The receivers also send feedback to the sender, and the sender uses this feedback to adjust the transmission rate for each channel. We present and analyze three different algorithms the sender might use for computing the transmission rates for each channel. Our analytical and simulation results show that this protocol achieves essentially optimal bandwidth utilization at the receivers.
['Hugh M. Smith', 'Matt W. Mutka', 'Eric Torng']
Bandwidth allocation for layered multicasted video