Improved Approximation Algorithms for Broadcast Scheduling

We consider two scheduling problems in a broadcast setting. The first problem is that of minimizing the average response time of requests. For the offline version of this problem we give an algorithm with an approximation ratio of O (log2(T +n)), where n is the total number of pages and T is the time horizon (arrival time of the last request). This substantially improves the previously best known approximation factor of O ( ) for the problem [3].

Our second result is for the throughput maximization version of the broadcast scheduling problem. Here each request has a deadline and the goal is to satisfy the maximum number of requests by their deadlines. We give an algorithm with an approximation ratio of 5/6. This improves the previously best known approximation guarantee of 3/4 for the problem. [10].

By: Nikhil Bansal; Don Coppersmith; Maxim Sviridenko

Published in: RC23468 in 2004

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