Optimized Scheduling on Broadcast Disks

Abstract

Since the advent of wireless networks and portable computing devices, push-based data delivery has been discussed as an attractive communication framework for wireless environments. This paper focuses on the way of scheduling that leads to the minimum access delay for a hierarchical push-based data broadcast mechanism. This mechanism, called “Broadcast Disks”, partitions data items into a number of logical disks spinning at different speeds and superimposes the disks on a single broadcast channel. In this paper, we mathematically model the Broadcast Disks program generation and suggest concrete design principles for deciding (a) how many disks to use, (b) how to segment data items into disks based on the user access patterns, and (c) how to determine the relative spinning speeds for disks in order to minimize the average access delay. In addition, we present our simulation study that substantiates the optimality of the suggested algorithms with detailed analyses.