Idzikowski F.,TU Berlin |
Orlowski S.,Atesio GmbH |
Raack C.,ZIB |
Woesner H.,TU Berlin |
Wolisz A.,TU Berlin
Optical Switching and Networking | Year: 2011
We estimate potential energy savings in IP-over-WDM networks achieved by switching off router line cards in low-demand hours. We compare three approaches to react on dynamics in the IP traffic over time, Fufl, Dufl and Dudl. They provide different levels of freedom in adjusting the routing of lightpaths in the WDM layer and the routing of demands in the IP layer. Using MILP models based on three realistic network topologies as well as realistic demands, power, and cost values, we show that already a simple monitoring of the lightpath utilization in order to deactivate empty line cards (Fufl) may bring substantial benefits. The most significant savings, however, are achieved by rerouting traffic in the IP layer (Dufl). A sophisticated reoptimization of the virtual topology and the routing in the optical and electrical domains for every demand scenario (Dudl) yields nearly no additional profits in the considered networks. These results are independent of the ratio between the traffic demands and capacity granularity, the time scale, distribution of demands, and the network topology for Dufl and Dudl. The success of Fufl, however, depends on the spatial distribution of the traffic as well as on the ratio of traffic demands and lightpath capacity. © 2011 Elsevier B.V. All rights reserved.
Agency: European Commission | Branch: FP7 | Program: CP | Phase: ICT-2011.1.1 | Award Amount: 11.63M | Year: 2012
DISCUS will analyse, design, and demonstrate a complete end-to-end architecture and technologies for an economically viable, energy efficient and environmentally sustainable future-proof optical network. It will provide a revolution in communications networks applicable across Europe and the wider world exploiting to the full the opportunity offered by LR-PONS and flat optical core networks to produce a simplified and evolvable architecture which will be the foundation for communications for the long term future. The architecture will be ultra energy efficient, simple to operate, robust to new technology introduction and providing universal availability of bandwidth and features regardless of geographic location.This ideal is obtained by a clean-slate approach to the architectural design by universal application of optical technologies throughout the fixed network eliminating traditional demarcations of metro, regional, core and access. Thus our essential concept is to use advanced optical technologies throughout giving rise to economies of scale and allowing bandwidths and flexibility hitherto unimaginable.Specifically the DISCUS architecture will: scale gracefully and economically, over a common physical infrastructure, as FTTP drives bandwidth growth by three orders of magnitude or more. It will evolve from todays architectures, adopting future technologies while co-existing with earlier generations. A unique feature will be a Principle of Equivalence whereby all network access points have equal bandwidth and service capability including core bandwidths (10Gb/s to 100\Gb/s) delivered to the access edge. It will seamlessly integrate wireless and fixed optical networks, fully exploiting both technologies. It will enable a competitive and simple regulatory environment controlled by customers and users rather than network operators and service providers.DISCUS is therefore fully aligned with the objectives of ICT-2011.1.1 and directly addresses its targets.
Agency: European Commission | Branch: FP7 | Program: CP | Phase: ICT-2007.1.1 | Award Amount: 4.98M | Year: 2008
The SOCRATES project investigates the application of self-organisation methods, which includes mechanisms for self-optimisation, self-configuration and self-healing, as a promising opportunity to automate wireless access network planning and optimisation, thus reducing substantially the Operational Expenditure (OPEX) and improving network coverage, resource utilisation and service quality. Fundamental drivers for the deployment of self-organisation methods are the complexity of the contemporary heterogeneous access network technologies, the growing diversity in offered services and the need for enhanced competitiveness.\n\nSOCRATES technological focus is on the self-configuration and self-optimisation of site and radio resource management parameters of 3GPP Long Term Evolution (LTE). Directed by a set of use cases where the application of self-organisation methods are anticipated to have a significant potential, novel methods for efficient and effective self-organisation are developed, with due attention given to the retrieval and processing of the required measurements.\n\nSelf-organisation in wireless access networks is a challenging topic: besides the intrinsically difficult issues concerning measurement and control, the project faces highly complex systems with a multitude of tuneable parameters and intricate interdependencies.\n\nAs part of the project a validation and demonstration of the developed methods for self-organisation is carried out through extensive simulation experiments, assessing the achievable cost reductions and performance enhancements. The implementation and operational impact of the developed concepts and methods is investigated by analysing the residual radio network planning process, the operations, administration and maintenance architecture and the protocol interfaces.
Agency: European Commission | Branch: FP7 | Program: BSG-SME | Phase: SME-2011-1 | Award Amount: 1.24M | Year: 2011
ICT energy consumption is a growing concern. With an expected exponential growth in data transport, the communications infrastructure alone may soon become one of the largest energy consumers in the world. This trend has long been detected and is addressed at various levels. The first to respond were the equipment manufactures, and modern equipment is considerably more energy efficient than the one deployed a decade ago. Given the growth rates in mobile data traffic, better equipment alone will not suffice to successfully fight exploding energy demand. Its smarter use, exploiting inherent, yet not fully explored intelligence in the networks shall further improve energy efficiency. The objective of the GreenNets proposal is to tackle this challenge for cellular radio networks. This is to be done by developing sophisticated methods and tools in four directions: for analyzing the energy efficiency in existing deployments; for finding measures to improve the efficiency; for implementing those measures in dedicated software platforms; and for establishing the ability to migrate to more energy efficient radio network deployments in face of sharply rising mobile network traffic. The ambitious aims of the project call for R&D activities that will extend and complement the platforms, tools and methodologies already in the possession of the participating SMEs. In a nutshell, the research aims at establishing two complementing functionalities: First, an automated network management that continuously adapts network activity to match the spatial and temporal network traffic variations. This shall leverage better efficiency in the short-to-mid term. Second, the ability to optimize the evolution of network deployments such that they become even more energy efficient in the mid-to-long term. Both lines are compelling extensions of the businesses the three GreenNets SMEs make today.
Raack C.,atesio GmbH |
Garcia J.M.,Telefonica |
Wessaly R.,atesio GmbH
CTTE 2015 - 2015 Conference of Telecommunication, Media and Internet Techno-Economics, Proceedings | Year: 2015
In this paper, we evaluate the cost of wireless integration into an architecture based on long reach passive optical networks (LR-PON). We will demonstrate that including backhaul or fronthaul signals from antenna sites into existing LR-PON structures deployed for wired customers requires only marginal additional resources. We will also show that scenarios with remote radio heads and centralised base band units outperform distributed radio access networks mainly because of operational cost savings. © 2015 IEEE.
Raack C.,Zuse Institute Berlin |
Koster A.M.C.A.,RWTH Aachen |
Orlowski S.,Atesio GmbH
Networks | Year: 2011
In this article, we study capacitated network design problems. We unify and extend polyhedral results for directed, bidirected, and undirected link capacity models. Valid inequalities based on a network cut are known to be strong in several special cases. We show that regardless of the link model, facets of the polyhedra associated with such a cut translate to facets of the original network design polyhedra if the two subgraphs defined by the network cut are (strongly) connected. Our investigation of the facial structure of the cutset polyhedra allows to complement existing polyhedral results for the three variants by presenting facet-defining flow-cutset inequalities in a unifying way. In addition, we present a new class of facet-defining inequalities, showing as well that flow-cutset inequalities alone do not suffice to give a complete description for single-commodity, single-module cutset polyhedra in the bidirected and undirected case - in contrast to a known result for the directed case. The practical importance of the theoretical investigations is highlighted in an extensive computational study on 27 instances from the Survivable Network Design Library (SNDlib). © 2010 Wiley Periodicals, Inc.
Orlowski S.,Zuse Institute Berlin |
Orlowski S.,Atesio GmbH |
Wessaly R.,Zuse Institute Berlin |
Wessaly R.,Atesio GmbH |
And 2 more authors.
Networks | Year: 2010
This article describes the Survivable Network Design Library (SNDlib), a data library for fixed telecommunication networkdesignavailableathttp://sndlib. zib.de. In the current version 1.0, the library contains data related to 22 networks which, combined with a set of selected planning parameters, leads to 830 network design problem instances. In this article, we discuss the data concepts of SNDlib and describe a mathematical model for each design problem considered in the library. We also provide information on characteristic features and the origin of the SNDlib problem instances. © 2009 Wiley Periodicals, Inc.
Orlowski S.,Atesio GmbH |
Pioro M.,Warsaw University of Technology |
Pioro M.,Lund University
Networks | Year: 2012
This survey deals with computational complexity of column generation problems arising in the design of survivable communication networks. Such problems are often modeled as linear programs based on noncompact multicommodity flow network formulations. These formulations involve an exponential number of path-flow variables, and therefore require column generation to be solved to optimality. We consider several path-based protection and restoration mechanisms and present results, both known and new, on the complexity of the corresponding column generation (also called pricing) problems. We discuss results for the case of single link or single node failures scenarios, and extend the considerations to multiple link failures. Further, we classify the design problems corresponding to different survivability mechanisms according to the structure of their pricing problem. Eventually, we show that almost all the encountered pricing problems are hard to solve for scenarios admitting multiple failures, while a great deal of them are NP-hard already for single failure scenarios. © 2011 Wiley Periodicals, Inc.
Eisenblatter A.,Atesio GmbH |
Schweiger J.,Zuse Institute Berlin
Computational Management Science | Year: 2012
Mobile communication is taken for granted in these days. Having started primarily as a service for speech communication, data service and mobile Internet access are now driving the evolution of network infrastructure. Operators are facing the challenge to match the demand by continuously expanding and upgrading the network infrastructure. However, the evolution of the customer's demand is uncertain. We introduce a novel (long-term) network planning approach based on multistage stochastic programming, where demand evolution is considered as a stochastic process and the network is extended so as to maximize the expected profit. The approach proves capable of designing large-scale realistic UMTS networks with a time horizon of several years. Our mathematical optimization model, the solution approach, and computational results are presented. © 2012 Springer-Verlag.
Agency: European Commission | Branch: FP7 | Program: CP | Phase: ICT-2011.1.1 | Award Amount: 6.12M | Year: 2012
The SEMAFOUR project will design and develop a unified self-management system, which enables the network operators to holistically manage and operate their complex heterogeneous mobile networks. The ultimate goal is to create a management system that enables an enhanced quality of user experience, improved network performance, improved manageability, and reduced operational costs. SEMAFOUR aims at taking the operation and management of mobile wireless networks to the next level.The SEMAFOUR project will have two key objectives. The first objective is the development of multi-RAT / multi-layer SON functions that provide a closed control loop for the configuration, optimisation and failure recovery of the network across different RATs (UMTS, LTE, WLAN) and cell layers (macro, micro, pico, femto). Such coordinated adaptation of radio (resource management) parameters in different RATs and cell layers is imperative for the global optimisation of network performance.The second objective is the design and development of an integrated SON management system, which interfaces between operator-defined performance objectives and the set of multi-RAT / multi-layer SON functions. This will provide a unified view on the performance of the complex heterogeneous network environment and allow its efficient control and operation. This important new management system enables operators to move their operational focus towards a higher, more global level, which is more transparent to the specifics of the underlying network technologies and cellular layout.In order to assess the achievable improvements in terms of network performance and manageability, the developed solutions will be evaluated through extensive simulation experiments and visualised by a demonstration system.