Preface

Abstract

The current issue of the Journal of Telecommunications and Information Technology contains twelve papers. In their articles, the authors consider important problems related to modern telecommunications. The first paper entitled “Call-level Analysis of a Two-Link Multirate Loss Model based on a Convolution Algorithm” by Sagkriotis et al. presents a multirate teletraffic loss model of a two-link system that accommodates Poisson arriving calls from different service-classes. The model was worked out under assumption that each link has two thresholds and based on a convolution algorithm. The next two papers deal with Elastic Optical Networks. The paper by Kabaciński, Rajewski and Al-Tameemin entitled “Rearrangeability of 2x2 W-S-W Elastic Switching Fabrics with Two Connection Rates”, considers rearreangeable conditions for the 2x2 three-stage switching fabric of a W-S-W (Wavelength-Space-Wavelength) architecture for elastic optical switches. The authors present rearrangeable conditions and an appropriate control algorithm. (...)