Multicast protocols for scalable on-demand download

Previous scalable protocols for downloading large, popular files from a single server include batching and cyclic multicast. With batching, clients wait to begin receiving a requested file until the beginning of its next multicast transmission, which collectively serves all of the waiting clients that have accumulated up to that point. With cyclic multicast, the file data is cyclically transmitted on a multicast channel. Clients can begin listening to the channel at an arbitrary point in time, and continue listening until all of the file data has been received. This paper first develops lower bounds on the average and maximum client delay for completely downloading a file, as functions of the average server bandwidth used to serve requests for that file, for systems with homogeneous clients. The results show that neither cyclic multicast nor batching consistently yields performance close to optimal. New hybrid download protocols are proposed that achieve within 15% of the optimal maxi...

• Type: Conference
• Year: 2004
• Where: SIGMETRICS
• Authors: Niklas Carlsson, Derek L. Eager, Mary K. Vernon
• Keywords: Cyclic Multicast, Maximum Client Delay, Optimal Maximum Delay, SIGMETRICS 2004