Efficient and accurate solution of multiserver retrial systems with user impatience through the value extrapolation technique

The retrial phenomenon plays an important role in many types of communication networks, and therefore, it should not be ignored in their analysis. Unfortunately, these systems do not present an exact analytic solution, so it is mandatory to resort to approximate techniques in order to compute their performance parameters. To the best of our knowledge, although there is a wide literature related to retrial systems, all the approximate techniques appeared up to now are based in computing the steady states probabilities and, later, computing the desired performance parameters. In this paper we use another approach to solve the retrial system based on a different metric: the relative state values which appear in the Howard equations. A numerical evaluation is carried out to evaluate this new technique and we compare its performance with previous techniques. The obtained results show that the proposed solution greatly outperforms the previous approaches appeared in the literature not only in terms of accuracy but also in terms of computational cost.