Showing papers by "Miroslaw Klinkowski published in 2010"

A Novel Offline Physical Layer Impairments Aware RWA Algorithm With Dedicated Path Protection Consideration

Abstract: Physical layer impairments accumulate as light propagates through a lightpath in the transparent optical networks. Therefore, it is possible to provision a lightpath, while its quality of transmission (QoT) does not meet the required threshold. Considering the physical layer impairments in the network planning phase gives rise to a set of offline Impairments Aware Routing and Wavelength Assignment (IA-RWA) algorithms. There are very few offline IA-RWA algorithms that consider dedicated path protection demands. In this work we propose a novel offline IA-RWA algorithm, called Rahyab and perform a comparative performance evaluation study, which considers two enhanced algorithms from the literature. Simulation results indicates that demand pre-processing, diverse routing, and adaptive wavelength assignment are the main reasons of lower blocking rate of Rahyab algorithm compared to the selected algorithms.

JAVOBS: A Flexible Simulator for OBS Network Architectures

Abstract: Since the OBS paradigm has become a potential candidate to cope with the needs of the future all optical networks, it has really caught the attention from both academia and industry worldwide. In this direction, OBS networks have been investigated under many different scenarios comprising numerous architectures and strategies. This heterogeneous context encouraged the development of various simulation tools. In this paper we present our novel Java-based OBS network simulator called JAVOBS. We discuss its architecture, study its performance and provide some exemplary results that point out its remarkable flexibility. This flexibility should permit an easy integration of upcoming new network protocol designs but also support changing and evolving research goals.

Modelling and Performance Evaluation of a Translucent OBS Network Architecture

Abstract: Most research works in optical burst switching (OBS) networks do not take into account the impact of physical layer impairments (PLIs) either by considering fully transparent (i.e., using optical 3R regeneration) or opaque (i.e., electrical 3R regeneration) networks. However, both solutions are not feasible for different reasons. In this paper, we propose a novel translucent OBS network architecture which aims at bridging the gap between the transparent and opaque solutions. In order to evaluate its performance, two different joint regenerator placement and routing heuristics are provided. Simulation results show that our translucent network model achieves performance results as good as those obtained with an opaque solution but with considerably less regenerators.

Channel allocation in dense wavelength division multiplexing radio-over-fiber networks

Abstract: In this paper we address the problem of the Radio-over-Fiber (RoF) network design. In particular, we focus on a DWDM RoF network for which we formulate a maximal service RoF channel allocation (MSCA) problem. Although MSCA is a difficult problem, still it can be resolved for the network instances of some hundred of access points and users.

An analysis of Regenerator Placement strategies for a Translucent OBS network architecture

Abstract: Most research works in optical burst switching (OBS) networks do not take into account the impact of physical layer impairments (PLIs) either by considering fully transparent (i.e., using optical 3R regeneration) or opaque (i.e., electrical 3R regeneration) networks. However, both solutions are not feasible for different reasons. In this paper, we propose a novel translucent OBS (T-OBS) network architecture which aims at bridging the gap between the transparent and opaque solutions. In order to evaluate its performance, a formulation of the routing and regenerator placement and dimensioning problem (RRPD) is presented. Since such formulation results in a complex problem, we also propose several alternative heuristic strategies. In particular, we evaluate the trade-off between optimality and execution times provided by these methods. Finally, we conduct a series of simulation experiments that prove that the T-OBS network model proposed effectively deals with burst losses caused by the impact of PLIs and ensures that the overall network performance remains unaffected.

On the physical impairments constraint in OBS networks

Abstract: The introduction of sub-wavelength switching is one of the main objectives of the future transparent optical mesh networks. One strong candidate is Optical Burst Switching (OBS) which improves the resource utilisation by setting up very short lived circuits (bursts). Nonetheless, introducing optical transparency in the optical layer has an important impact on the network performance. In fact, the signal propagates through a transparent optical path accumulates the effect of a variety of quality degrading phenomena which limits the system reach. Translucent optical networks are emerging as a promising solution for bridging the gap between opaque and transparent networks. In this paper we investigate these alternatives in OBS networks and test the effectiveness of the translucent solution.

Optical transmission impairments in 60 GHz radio-over-fiber system

Abstract: In this paper we address the problem of the impairments in Radio-over-Fiber (RoF) transmission which occur in an optical link in a millimeter-wave (mm-wave) band, e.g. for 60 GHz carrier frequency. We carry out some basic relations between DSB, SSB and OSC modulation formats and than compare duobinary and RZ modulation by numerical simulations.

Trends and challenges in optical packet networking: The network layer perspective

Abstract: The immense growth of the Internet which is accompanied by the emergence of new communication technologies, applications, and devices, results in the evolution from voice-centric toward data-centric optical networks. In this paper we overview some of the trends in optical packet networking and identify several related research problems. Our particular focus is on the network layer aspects of future optical networks.