Backbone networks are evolving toward Elastic Optical Network (EON) architecture that allows a flexible and efficient use of spectrum resources. Flexibility in EONs is guaranteed also by emerging sliceable bandwidth variable transponders (SBVTs) that support the simultaneous generation of multiple optical carriers. Such carriers can be used to serve different lightpaths (i.e., slice-ability), o...

Motivated by WiFi channel assignment, we propose and explore two vertex-coloring problems for graphs, where the spectrum of colors is endorsed with a matrix of interferences between each pair of colors. The Threshold Spectrum Coloring problem fixes the number of colors available and aims to minimize the interference threshold, i.e., the maximum of the interferences at the vertices. The Chromati...

This paper proposes a distributed and fair resource allocation scheme for large-scale wireless dynamic spectrum access networks based on particle filtering theory. We introduce a proportionally fair global objective function to maximize the total network throughput while ensuring fairness among users. We rely on particle filtering theory to enable distributed access and allocation of spectrum r...

Cognitive Radio has the colossal key system of empowering range observed in the Spectrum detection. This paper manages spectrum detecting strategy utilizing wavelength which partitions a part of Cognitive radio arrangement burdens and introduces focal points confronting mostly all detecting problem for low gain SU by merging cyclic frequency with assignments. Subjective radio confronting numero...

Distance adaptive spectrum allocation exploits the tradeoff between spectrum width and reach to improve resource utilization by tailoring the modulation format to the level of impairments along the path. We first show that the the distanceadaptive routing and spectrum assignment (DA-RSA) problem in mesh networks is a special case of a multiprocessor scheduling problem. We then develop a suite o...

Dynamic spectrum sharing approach is a paradigm shift from the conventional static and exclusive approach to spectrum allocation. The existing methodologies to define use of the spectrum and quantify its efficiency are based on the static spectrum assignment paradigm and not suitable for the dynamic spectrum sharing paradigm. There is a need to separately quantify the spectrum consumed by the i...

Nowadays the demand of the wireless application has grown from day to day life. The Demand of wireless applications has put a many of constraints on the use of available radio spectrum which is a limited and precious resource. The static spectrum assignment leads to underutilization of the spectrum as a great portion of the licensed spectrum is not efficiently utilized. Cognitive radio (CR) is ...

In this paper, we investigate the issue of spectrum assignment in CRNs and examine various opportunistic spectrum access approaches proposed in the literature. We provide insight into the efficiency of such approaches and their ability to attain their design objectives. We discuss the factors that impact the selection of the appropriate operating channel(s), including the important interaction ...

Today’s wireless networks are characterized by fixed spectrum assignment policy. The limited available spectrum and the inefficiency in the spectrum usage necessitate a new communication paradigm to exploit the existing wireless spectrum opportunistically. Cognitive radio is a paradigm for wireless communication in which either a network or a wireless node changes its transmission or reception ...