Nonrate-proportional weighting of generalized processor sharing schedulers

This paper is concerned with GPS-based packet schedulers which are very important elements of guaranteed QoS networks. After recalling the basic properties of generalized processor sharing we introduce a novel approach to calculate tighter delay bounds than given in the former works of Parekh et al. (1993, 1994). This not only allows better utilization of networks resources but supports basis for arbitrary weighting of sessions. An efficient and numerically inexpensive algorithm for computing these bounds is also presented herein. Further we relax the rate-proportional weighting constraint and show that our delay bound calculation is applicable for any arbitrary (nonrate-proportional) weighted GPS system. Numerical examples demonstrate the flexibility of our algorithm in terms of adjusting delay and bandwidth easily between theoretical bounds. This approach is a very important step towards avoiding bandwidth-delay coupling which is a well-known problem of GPS-based rate-proportional servers.