Soutenance de thèse de M. Özgür Can TURNA
le 30 janvier 2014 en salle A003 (Visio Centre) à 14h30.
« Bandwidth Allocation and Energy Efficiency Solutions in Optical Access Networks »
Le jury :
- Philippe GRAVEY Rapporteur Directeur d’étude à Telecom Bretagne
- Dominique CHIARONI Rapporteur Chercheur Senior (Team Leader) à Alcatel-Lucent France
- Serge FDIDA Examinateur Professeur à l’université Pierre et Marie Curie
- Nihal PEKERGIN Examinateur Professeur à l’université Paris Est Créteil Val de Marne
- Catherine LEPERS Examinateur Professeur à Telecom SudParis
- Hakima CHAOUCHI Examinateur Professeur à Telecom SudParis
- Tülin ATMACA Directrice Professeur à Telecom SudParis
- Halim ZAİM Co-encadrant Professeur à l’université d’Istanbul
Le résumé :
By the developments in information technologies, service providers try to reach as much subscribers as they can with lower costs. Optical networks are distinguished as a solution to solve increasing bandwidth demand and error free data transmission over long haul. Passive Optical Network (PON) is known to be the best choice in optical access network solutions. PON consists of Optical Line Terminals (OLT) at central office, Optical Network Unit (ONU) at user side, passive splitters and optical fibers between them.
In this study, general overview about PON systems is presented and existing PON mechanisms and classifications are investigated. After the general overview of PONs, a novel dynamic bandwidth allocation algorithm for EPON is introduced. This proposed algorithm is named as “Half Cycling Dynamic Bandwidth Allocation-hcDBA” by the inspiration of its half cycling processing mode. Later, an improvement of hcDBA algorithm with early prediction mechanism is presented. The simulated traffic behavior of EPON’s upstream channel has been investigated in order to support the decision of traffic generator in further studies. The newly proposed algorithm have been implemented on NS2 simulation tool and compared to existing EPON dynamic bandwidth allocation algorithms. The comparison results and performance analysis are given for mono-service and multi-service cases for 1 Gbps and 10 Gbps link capacities. As a result statement of the study, hcDBA algorithm performs better than existing mechanism in terms of byte loss ratio and access delays.
Energy conservation is one of the hot topics in telecommunication networks. Access networks constitute a remarkable portion of the total energy consumption in telecommunication networks. ITU-T and IEEE organizations published recommendation for energy conservation in PONs. While, total energy consumption of ONUs is more than other equipment in fix access network the standards and most of the researches focused on saving energy at ONU side. In this thesis I focused on an energy efficiency method based on energy conservation on OLT side. The proposed method save energy by dynamically passing OLT cards to deep sleep mode according to the incoming and outgoing traffic loads.