Linearizer

The topic of this special issue is Solution Techniques for Queueing Network Models.There are three papers, each describing a different approach to the solution of queueing networks.The paper by Zahorjan et al. was selected as the best paper of the SIGMETRICS Symposium on Measurement Modeling and Evaluation of Computer Systems, held at the University of Nevada, Las Vegas, on September 14-16, 1981.This paper builds on earlier work on estimating bounds on system performance as a function of the load.The current paper presents tighter bounds than were previously available.All of the other papers on the symposium program appear in the Proceedings, which is available at ACM Headquarters.The paper by Chandy and Neuse is a significant contribution to obtaining solutions of models with large numbers of facilities and/or customers and classes of customers.It too extends earlier work.The current paper promises greater accuracy while retaining relatively short solution times.The final paper, by Jacobson and Lazowska, presents a new technique for obtaining approximate solutions of a class of models that could not be accurately solved.Since actual systems have many instances of simultaneous resource possession, this new technique could prove to be a valuable addition to the field.The several reviewers of these papers plus the members of the program committee for the SIGMETRICS conference all contributed to the appearance of these papers.The editor wishes to express his gratitude for their efforts.