On maximizing service-level-agreement profits

We present a methodology for maximizing profits in a general class of e-commerce environments. The cost model is based on revenues that are generated when Quality-of-Service (QoS) guarantees are satisfied and on penalties that are incurred otherwise. The corresponding QoS criteria are derived from multiclass Service-Level-Agreements (SLAs) between service providers and their clients, which include the tail distributions of the per-class delays in addition to more standard QoS metrics such as throughput and mean delays. Our approach consists of formulating the optimization problem as a network flow model with a separable set of concave objective functions based on queueing-theoretic formulas, where the SLA classes are taken into account in both the constraints and the objective function. This problem is then solved via a fixed-point iteration. Numerous experiments illustrate the benefits of our approach.