Improved Approximation Algorithms for Broadcast Scheduling

Improved Algorithms for Scheduling Data Broadcast

With the increasing popularity of portable wireless computers, mechanisms to eeciently transmit information to such clients are of signiicant interest. The environment under consideration is asymmetric in that the information server has much more bandwidth available, as compared to the clients. It has been proposed that in such systems the server should broadcast the information periodically. A...

Improved approximation algorithms for scheduling parallel jobs on identical clusters

The Multiple Cluster Scheduling Problem corresponds to minimize the maximum completion time (makespan) of a set of n parallel rigid (and non-preemptive) jobs submitted to N identical clusters. It cannot be approximated with a ratio better than 2 (unless P = NP). We present in this paper the methodology that encompasses several existing results [1, 2]. We detail first how to apply it for obtaini...

Improved Approximation Algorithms for Minimum-Space Advertisement Scheduling

Improved approximation algorithms for scheduling with fixed jobs

We study two closely related problems in non-preemptive scheduling of sequential jobs on identical parallel machines. In these two settings there are either fixed jobs or nonavailability intervals during which the machines are not available; in either case, the objective is to minimize the makespan. Both formulations have different applications, e.g. in turnaround scheduling or overlay computin...

Approximation Algorithms for Minimum Time Broadcast

This paper deals with the problem of broadcasting in minimum time in the telephone and message-passing models. Approximation algorithms are developed for arbitrary graphs as well as for several restricted graph classes. In particular, an O(vfvT)-additive approximation algorithm is given for broadcasting in general graphs, and an O(log n/ log log n) (multiplicative) ratio approximation is given ...