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Photonic Networks; 12. ITG Symposium; Proceedings of

Date 2-3 May 2011

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Displaying Results 1 - 25 of 27
  • Agile optical networks from access to core

    Page(s): 1 - 4
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (956 KB)  

    Optical transport is the only technology providing the necessary reach and capacity to make today¿s and tomorrow's telecommunication networks possible. Recent progress will leverage this technology to greatly simplify network structures, to reduce complexity of network planning and operations, and to increase agility of the overall transport network. Next Generation Optical Access (NGOA) will simplify backhaul by making aggregation equipment and many equipment sites obsolete. Packet Optical Transport Systems (POTS) will condense network layers into a converged network for wavelength, circuit and packet transport and switching and therefore enable simpler end-to-end control of transport services. View full abstract»

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  • 100GET / OCTET Success Stories - Results of 100 Gbit/s Field Experiments in the Deutsche Telekom Network Infrastructure

    Page(s): 1 - 4
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1368 KB)  

    In the framework of the BMBF / Celtic funded program 100GET, the OCTET (Open Environment for Advanced Carrier Ethernet Technologies) project provided a test environment for 100 Gbit/s solutions of different partners in the already installed fiber infrastructure of Deutsche Telekom in Germany. The project was well in time with the development of 100 Gbit/s client and transport network interface technologies, standardized at IEEE 802.3ba for 100GE Ethernet, and at ITU-T G.709 for 100G OTN, respectively. Additionally, long haul 100 Gbit/s DWDM transmission technologies have been specified in a multi source agreement of the Optical Internet Forum. However, the goal of the project was to investigate 100 Gbit/s solutions which can be deployed in DWDM channels of field installed packet/optical transport networks, supporting the development of cost efficient and scalable Terabit/s transmissions. Since the project finished in December 2010, in this paper we summarize the work and present the main results and conclusions. View full abstract»

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  • WDM transport towards Terabits/s line rates - what will be gained?

    Page(s): 1 - 6
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (412 KB)  

    Since per-channel data rates of 100 Gb/s have become available in commercial optical transport systems, research efforts are now targeted at the next step in high-speed channel rates, which likely will be in the 400 Gb/s and/or 1 Tb/s range. In this presentation, we investigate various optical transmission schemes and modulation formats which will enable this step while maintaining moderate requirements on electrical and optical component technology. Based on optical noise tolerance criteria and taking into account optical power limitations as well as non-linear fiber effects to a certain extent, multiple subcarriers modulated with dual-polarization quaternary phase-shift keying (DP-QPSK) will give a capacity-times-reach product comparable to 100-Gb/s channel rates. This is true for both 400 Gb/s and 1 Tb/s channel rates. However, the use of more advanced modulation formats, like polarization-switched (PS-) QPSK can improve this measure by 50%. For shorter reach applications like metro networks or data center connectivity, higher-order modulation formats can improve the spectral efficiency of the signals. These different applications are investigated, and technologies are proposed to achieve the next steps in high data-rate optical transmission. View full abstract»

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  • Integrated Coherent Receiver Modules for 100G Ethernet and Beyond

    Page(s): 1 - 5
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (918 KB)  

    We report on recent measurements of integrated coherent receiver modules for 100G Ethernet transport. In system experiments with up to 160-Gb/s PDM-QPSK signals and 224-Gb/s PDM-16QAM signals their potential for detection of high symbol rate signals and higher order modulation formats is demonstrated. Furthermore, a new fully integrated polarization-diversity coherent receiver module comprising a micro-optic polarization beam splitter and two InP-based 900 hybrids with integrated photodiodes is characterized using 112-Gbit/s PDM-QPSK signals. View full abstract»

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  • Synchronous 16-QAM Transmission in a FPGA-Based Coherent Receiver with Different Phase Estimation Filter Lengths

    Page(s): 1 - 3
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (514 KB)  

    In this article we present the implementation of a 16-QAM transmission system with feedforward realtime synchronous demodulation and data recovery. Different filter lengths (half-width N) were evaluated and a realtime data throughput of 2.5 Gbit/s was achieved. The 625 Mbaud (4x625 Mb/s) data is transmitted over one span of single-mode fiber, and is received in a realtime I&Q homodyne setup with standard external cavity laser. For powers larger than -30dBm, the average bit error rate (BER) is below forward-error correction (FEC) limit (7% overhead). View full abstract»

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  • Coherent Detection using Parallel Optical Sampling

    Page(s): 1 - 5
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1050 KB)  

    We discuss a coherent receiver scheme exploiting optical sampling to overcome the speed limitations of electronic analog-to-digital converters. Digital coherent receivers with aggregate optical sampling rates of up to 112 GSa/s are realized experimentally. The performance of such receivers is investigated in transmission experiments. Transmission of 56 GBd quadrature phase-shift keying signals over 610 km standard single-mode fiber and coherent detection with electronic impairment mitigation is demonstrated. The employed electrical analog-to-digital converters have only 20 GHz bandwidth and a sampling rate of 50 GSa/s. View full abstract»

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  • Clock Recovery in Coherent Optical Receivers

    Page(s): 1 - 4
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (390 KB)  

    Standard clock recovery schemes with timing phase estimation before or after the 2x2 MIMO FIR filter in digital coherent receivers are analyzed. In particular, the influence of first-order PMD combined with certain SOPs to the timing estimation is investigated. No scheme has been identified to prove robust timing estimation for all channel conditions. View full abstract»

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  • Requirements and Solutions for Next-Generation Access

    Page(s): 1 - 8
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (515 KB)  

    Next-generation access systems will have to provide sustained bandwidths in excess of 100 Mb/s per residential customer, in conjunction with increased reach in the range of 20 to 60 km. In addition, low energy consumption and ease of installation and operation are required. Many potential solutions have been proposed which range from Active to Passive Optical Networks. We provide an analysis of possible solutions, with focus on Passive Optical Networks. View full abstract»

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  • Impact of strategic decisions on the planning of FTTx-Networks: A case study

    Page(s): 1 - 5
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1444 KB)  

    We present research results achieved in the framework of FTTX-PLAN, a project partially funded by the German Federal Ministry for Education and Research. The goal of this project is to develop tools and methods that support the automated planning and optimization of FFTx networks. Such methods enable to optimize the network infrastructure with regard to capital expenditure (CAPEX) by selecting the optimal locations for central offices, fiber collects, distribution points as well as trails between them. These methods can also provide useful insights to help taking strategic decisions such as the choice of technology, optimal penetration rate or consideration of upgradability scenarios before the actual planning process takes place. In this paper we first give an overview of the methods developed in FTTX-PLAN and briefly present how they can be used for the planning and optimization of FTTx networks. We then review the different strategic decisions in FTTx planning and illustrate their impact by means of a use case of the roll-out of FTTx networks in urban or rural areas. View full abstract»

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  • Impact of protection to capital and operational expenditures of optical access networks

    Page(s): 1 - 6
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1161 KB)  

    Reliability is becoming a crucial issue for service providers, operators and users in optical access networks. The increase of network capacity and the importance of reducing service interruption times, force network operators to implement protection mechanisms in optical access networks. However, so far providing backup resources in access networks has been considered too expensive. In order to assess the impact of protection on capital and operational expenditures, the evaluation needs to study the impact to aspects such as the required infrastructure and equipment costs, failure reparation costs, and expected service interruption time. This work deals with the cost and reliability evaluation of time-division-multiplexing (TDM) and wavelength-division-multiplexing (WDM) passive optical networks (PONs). Three strategies to offer protection are evaluated: 1) provide protection in the access network directly from the greenfield, 2) invest initially on an unprotected architecture keeping in mind a future upgrade with protection resources, and 3) roll out an unprotected access network and if needed in the future, invest in deployment of protection resources. The impact of these strategies on the overall cost is studied. View full abstract»

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  • Overview of Optical Monitoring in Next Generation Optical Access Networks

    Page(s): 1 - 7
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (786 KB)  

    Next generation optical access networks are considered as key technology for future optical networks to generally cover the emerging high demand for bandwidth and data rates. As the reliance to the physical infrastructure of the network grows, a powerful monitoring and maintenance system forms the basis of an efficient network management to guarantee reliability and to meet a certain service level agreement. The increase of splitting ratio and transmission distance of next generation optical access networks is leading to novel requirements for monitoring systems. This paper gives a general overview of optical monitoring systems based on optical time domain reflectometry. Different monitoring solutions are compared and their suitability for next generation optical access networks is discussed. Specific limitations and challenges for monitoring in next generation optical networks are emphasized. View full abstract»

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  • 100Gbit/s IP-Router and DWDM Transmission Interoperability Field Tests

    Page(s): 1 - 3
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (828 KB)  

    The ongoing capacity demand in the communication networks led to the development of 100Gbit/s technologies standardized at IEEE 802.3ba for 100GE Ethernet and at ITU-T G.709 for 112 Gb/s optical transport network (OTN) interfaces. Such multi-lane interfaces became recently commercially available as pluggable CFP modules, which are well suited in data centers and central offices for IP routers and switches, and for the client or tributary side of long haul OTN transmission systems. For the line side of long haul 100Gbit/s DWDM transmission systems, the polarization multiplex - quadrature phase shift keying - coherent detection (PM-QPSK-CD) technology was proposed in a multi source agreement of the Optical Internet Forum (OIF). In this paper the 100 Gbit/s interworking between IP routers, long haul DWDM transponders, a field installed DWDM transmission system, and an IP performance tester is discussed and successfully demonstrated by R&D field experiments in the German Deutsche Telekom network, also enabled by the 100GET project. In the tests, IP routers of Alcatel-Lucent, Cisco, and Juniper were interconnected via e.g. 100GBASE-LR4 pluggable CFP transceiver modules to the IXIA IP performance tester, and to the 112 Gbit/s DWDM transponders of Alcatel-Lucent and Huawei. Those 3rd party DWDM transponders used DWDM channels of an already field installed Ericsson DWDM transmission system of 220 km link length between Essen and Muenster. The 100G IP and DWDM interoperability tests were successfully performed together with co propagating 10G NRZ, 10G RZ, and 40G NRZ channels in the DWDM system, enabling migration scenarios towards Tbit/s link capacities. Furthermore, the already installed fiber DWDM infrastructure could be used by 3rd party equipment for management assigned alien wavelength channels, enabling modular network architectures with Plugï¿¿ï¿¿ï¿¿ Play functionality, and cost effective networking by combining optic and packet functionalities. View full abstract»

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  • Metro Field Trial of 100 Gb/s Channel Transmission over Mixed-Fiber with Real-Time Data Processing

    Page(s): 1 - 4
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1162 KB)  

    We present results from a transmission field trial for a cost-efficient 107 Gb/s channel using real-time data processing. The channel bit error ratio (BER) was sufficient for error-free performance after FEC for a 150 km mixed SSMF and DSF metro route in the Berlin area as part of the OCTET test bed. The DPSK-3ASK modulation format used in the trial was investigated as a lower-cost, metro-focused alternative to the DP-QPSK format, and was assembled using commercially available serializer and deserializer ICs and FPGA. Transmission results as well as latency measurements over a pair of 10GbE tributaries are described. Additionally, post-trial laboratory results for transmission distances up to 430 km with standard single-mode fiber are presented. View full abstract»

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  • Operational Concept for Future Optical Networks

    Page(s): 1 - 4
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (422 KB)  

    The basic transport service provider business is about the provision of connectivity, a commodity facing cost pressure due to little potential for differentiation. Concepts like on-demand provisioning, inter-domain provisioning or provisioning of whole topologies (virtual networks) have the ability to improve competitive positioning, but as the number of concurrent users of a network infrastructure increases this will also cause significant demand fluctuations. As a result, future optical networks will ultimately have to deal with frequent reconfiguration of transport tunnels on different levels of granularity. An operational concept is proposed which is centered around the Generalized Multiprotocol Label Switching (GMPLS) Control Plane approach and solves both fluctuation and differentiation issues. It is shown that embracing the existing Control Plane standards as much as possible provides a smooth evolution path from network automation to network virtualization. View full abstract»

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  • Robustness in Communication Networks: Scenarios and Mathematical Approaches

    Page(s): 1 - 8
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (704 KB)  

    The planning of wide-area networks to achieve robust operation is an ongoing challenge for network providers. Robust means to ensure stable operation of a network in case of fault occurrence. In this paper several scenarios in the context of the German Research Network are discussed to point out robustness aspects in a more detailed manner. The approach to address these challenges is to apply mathematical methods, more precisely exact and approximate integer linear programming and fast combinatorial algorithms. View full abstract»

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  • Managing flexible WDM Networks End-to-End

    Page(s): 1 - 3
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (251 KB)  

    Building networks have for a long time been based on electrical switching technologies and dumb optical fiber interconnect. However with optical switching technology new networking capabilities have evolved that offer lower cost per bit and better economy of scale. On the other side, maintenance and survivability of such networks is impacted by the nature of optical technology. This requires a new approach to control networks that are based on Next Generation WDM comprising optical and electrical switching. In the past, transport networks have been built considering strict layering inside a single technology like SDH-Higher Order and SDH-Lower Order switching. Now the new networking paradigm is based on a hybrid technology that correlates information available on electrical and optical switching functions to compensate for the lack of information that can be derived from a wavelength along the route. This correlation is provided by a multi-layer control plane that allows to operate the WDM network as if it would be a network based on a dual layer electrical switching technology thereby saving OPEX by integration. View full abstract»

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  • Architectures for Multiband Multi Gbps Radio-over-Fiber Systems

    Page(s): 1 - 5
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1137 KB)  

    An overview over all elements of a Radio over Fiber (RoF) system is provided including optical transmitter, fiber optic link, wireless link and millimeter wave receiver. The influence of the wireless link on the data capacity of the RoF link is analyzed using Shannon¿s theoretical limit. To include the influence of the fiber optic link the consequences of chromatic dispersion and PMD for the link budget are discussed for different modulation schemes. On that basis different system approaches for the optical transmitter for Multi Gbps communications are presented and evaluated including a concept for multiband-millimeter-wave generation based on an optical frequency comb. The multiband concept will be presented and evaluated in comparison to the alternative approaches on a system level. Together with the demonstration of two different receiver concepts the paper offers a comprehensive guideline for the design of Radio over Fiber systems for the convergence of wireless and fiber optic broadband user access. View full abstract»

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  • Möglichkeiten und Grenzen von Terahertzwellen fÿr zukÿnftige Kommunikationssysteme

    Page(s): 1 - 5
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (399 KB)  

    Die Kapazitï¿¿ï¿¿t der ï¿¿ï¿¿bertragungskanï¿¿ï¿¿le - also die maximale Datenrate, die ï¿¿ï¿¿ber einen Kanal ï¿¿ï¿¿bertragen werden kann - stellt fï¿¿ï¿¿r den bisherigen Verkehrsbedarf keine Begrenzung dar. Daher reichte die Entwicklung von Technologien zur spektral effizienten Modulation und zur Verringerung des Rauschens oder der Verzerrungen bislang aus, um die derzeitigen Datensteigerungsraten von ca. 40 % pro Jahr abdecken zu kï¿¿ï¿¿nnen. In letzter Zeit kommen aber sowohl im Radiofrequenzbereich als auch bei der optischen Kommunikation in photonischen Netzen mï¿¿ï¿¿gliche Grenzen in Sicht. So wurden auf der OFC 2010 mit derzeitigen Spitzentechnologien (z. B. spektral effiziente Modulationsformate, verteilte Ramanverstï¿¿ï¿¿rkung, Unterdrï¿¿ï¿¿ckung nichtlinearer Effekte ï¿¿ï¿¿ber die nichtlineare Schrï¿¿ï¿¿dinger-Gleichung) Datenï¿¿ï¿¿bertragungsraten gezeigt, die bereits an die Kapazitï¿¿ï¿¿tsgrenze der weltweit verlegten Glasfasern stoï¿¿ï¿¿en. Eine Sï¿¿ï¿¿ttigung der stetigen Datenratensteigerungen ist nicht in Sicht. Um auch zukï¿¿ï¿¿nftig den Kapazitï¿¿ï¿¿tsbedarf fï¿¿ï¿¿r die weltweite Kommunikation und die breitbandige Konnektivitï¿¿ï¿¿t portabler Endgerï¿¿ï¿¿te bereitstellen zu kï¿¿ï¿¿nnen, werden daher vï¿¿ï¿¿llig neue Ansï¿¿ï¿¿tze benï¿¿ï¿¿tigt. Eine Mï¿¿ï¿¿glichkeit erï¿¿ï¿¿ffnet dabei die Nutzung bisher unerschlossener Frequenzbereiche fï¿¿ï¿¿r die Datenï¿¿ï¿¿bertragung. So steht eine groï¿¿ï¿¿e, bisher fast ungenutzte Bandbreite im Terahertz (THz)-Bereich zur Verfï¿¿ï¿¿gung. Gleichzeitig bieten THz-Wellen ï¿¿ï¿¿bertragungseigenschaften, die zwischen denen von Radio- und optischen Wellen liegen und erï¿¿ï¿¿ffnen damit neue Mï¿¿ï¿¿glichkeiten fï¿¿ï¿¿r die breitbandige Kommunikation. Insbesondere sind Applikationen mit GHz Bandbreiten ï¿¿ï¿¿ber bisher unregulierte spektrale Resourcen mï¿¿ï¿¿glich. In diesem Beitrag werden die physikalischen Eigenschaften der THz-Wellen unter dem Gesichtspunkt der Datenï¿¿ï¿¿bertragung beleuchtet. Es wird ein ï¿¿ï¿¿berblick ï¿¿ï¿¿ber bisherige Projekte zur Ausnutzung dieses Frequenzbereichs gegeben und es werden Wege aufgezeigt, wie sich THz-Wellen fï¿¿ï¿¿r zukï¿¿ï¿¿nftige Kommunik- tionssysteme nutzen lassen kï¿¿ï¿¿nnten. View full abstract»

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  • Mode Division Multiplexing using Principal Modes as Carriers in MMFs with Different Number of Guided Modes

    Page(s): 1 - 5
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1152 KB)  

    We investigate the concept of mode division multiplexing (MDM) in multimode fibers (MMF) using so called principal modes (PM) as carriers. Some of the challenges when using PMs as carriers are presented and their impact on MDM transmission are analyzed. An eye opening penalty criteria of 2dB is used to quantify the usability of each PM for MDM operation as a function of number of guided eigenmodes in the MMF. Simulations show that the amount of usable PMs are highly dependent on mode coupling strength and do not necessarily increase as the number of eigenmodes increase in the MMF. View full abstract»

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  • Parametric Amplification as an Option for Optical Broadband Amplification

    Page(s): 1 - 8
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1151 KB)  

    Optical parametric amplification (OPA) will be discussed as an option for optical broadband amplification beside Erbium-doped fiber amplifiers (EDFA) and distributed Raman amplification (DRA). Fiber-based OPAs rely on the nonlinear effect of four-wave mixing (FWM) that occurs in silica fibers due to the underlying Kerr effect. The amplification of the input signal is realized by an energy transfer from one or two pump waves. High gain (> 30 dB) with pump powers < 1 W is yielded using special highly-nonlinear fibers (HNLF) that provide a small effective area and therefore high power densities. The largest advantage of OPAs against EDFAs is the flexibility of the gain spectrum. Both the center wavelength (e.g. S-, C-, L-band) and the bandwidth ( > 50 nm) of the amplifier can be adjusted by appropriately engineering the dispersion profile of the HNLF and by the choice of the pump signal(s) wavelength(s). Because of the low-loss coupling to the standard single-mode fiber and the inherently low-noise amplification, noise figures similar to EDFAs (> 4 dB) can be realized. A disadvantage is the polarization-dependence of the FWM process that has to be mitigated by polarization-diversity schemes. The usage of a HNLF-based loop which relies on the counter-propagation of the both signal polarizations is discussed in detail and results of system experiments using directly-detected 112 Gb/s-PolMux-DQPSK signals are presented. Furthermore, FWM is always accompanied by self- and cross-phase modulation (SPM and XPM). Due to the ultrafast response time of the Kerr nonlinearity, both effects can lead to distortions of the signal phase. This is discussed in detail and system experiments using coherently-detected 112-Gb/s 16QAM signals are presented. View full abstract»

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  • Investigation of Wavelength Control Schemes in WDM-PONs

    Page(s): 1 - 5
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (572 KB)  

    WDM-PON based on low-cost tunable lasers is a promising candidate for next-generation broadband optical access. For cost reasons, the tunable lasers must not be equipped with dedicated coolers and wavelength lockers. Then, correct tuning of the lasers must be ensured by cost-effective tuning mechanisms which are implemented and shared in the system context. In this paper, we describe several approaches to WDM-PON and how wavelength locking can be implemented. View full abstract»

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  • Network Design Under Demand Uncertainties: A Case Study on the Abilene and GÉANT network data

    Page(s): 1 - 8
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (500 KB)  

    Traffic in communication networks fluctuates heavily over time. Thus, to avoid capacity bottlenecks, operators highly overestimate the traffic volume during network planning. Often, expensive safety factors of 300% or more are applied to the link capacity. In this paper, we consider telecommunication network design under demand uncertainty, adopting the robust optimization approach of Bertsimas and Sim. This deterministic approach provides an adjustable uncertainty and preserves the computational complexity of the original non-robust problem. Recently, Koster et al. have applied this approach to network design problems. Using detailed real-life traffic measurements of the US Internet 2 (Abilene) and the pan-European research and education network (GEANT) backbone networks, we present an extensive computational case study for this so-called Gamma-robust network design problem. For each network, we determine optimal robust network designs for 198 different parameter settings. Afterwards, we evaluate the realized robustness of these designs with respect to (i) the traffic measurements used as planning data, and (ii) a larger set of traffic measurements including the planning data to simulate uncertain future traffic. We give different robust measurements (e. g., the percentage of supported traffic matrices, or the percentage of congested links) and compare the corresponding realized robustnesses. We report on the importance of statistical input data analysis to determine reasonable parameter settings for robust network planning. Further, by determining pareto-optimal parameter settings based on the price of robustness and the evaluated realized robustness, our analysis provides practical decision support criteria for network planners. View full abstract»

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  • Analysis of the Energy Efficiency in IP over WDM Networks with Load-Adaptive Operat

    Page(s): 1 - 7
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1396 KB)  

    The energy efficiency of telecommunication networks has gained increasing interest during the recent past. Since the traffic volume in networks is observed to vary significantly over time and current telecommunication networks provide approximately constant capacity, energy-aware load-adaptive operation of telecommunication networks with respect to that real traffic load characteristics is a promising approach for improved network energy efficiency and sustainability. By means of real traffic measurement data the potential of increasing the related energy efficiency is studied. The analysis shows an energy saving potential that can be leveraged by load-adaptive operation of about 6-7 % compared to the reference network with conventional operation. View full abstract»

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  • Load Adaptive Optical-Bypassing for Reducing Core Network Energy Consumption

    Page(s): 1 - 5
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (582 KB)  

    We study dynamic reconfiguration of a core IP/MPLS-over-WDM network for adaption to traffic patterns changing during the course of the day. Our approach tries to route the traffic preferably in the optical layer and deactivates unused IP router ports. Our results show up to 57 % reduction of power consumption in low-load periods by load adaptive optical-bypassing and deactivation of network element subsystems. View full abstract»

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  • All optical Quasi Light Storage: achievements and limitations

    Page(s): 1 - 4
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (640 KB)  

    In this paper we consider the achievements and limitations of two methods for delaying the optical signals based on quasi light storage (QLS). These methods are very simple and offer high tunable storage times up to several thousand bits. We explore the potentials and limitations of both methods. Fiber based QLS is useful when high absolute delay is required and very small amounts of attenuation can be tolerated. Frequency-to-time-conversion based QLS can be used for delaying of very high bandwidth signals. View full abstract»

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