Objectif The aim of WOTAN is to provide a managed, end-to-end wavelength-agile optical communications system for public telecommunications networks. Wavelength agility across a large number of closely spaced wavelengths increases the bandwidth capacity of the network, and enhances traffic management flexibility. WOTAN will investigate the optimum mix of optical and electronic solutions for switching and networking, across both access and core, to provide an integrated, managed network platform, that maximises the evolutionary potential of the network.A major objective of the WOTAN project is to understand and demonstrate how core and access networks can be effectively integrated through the common use of WDM (wavelength-division-multiplexed) channels. A second aspect is the use of wavelength agility; thus for example different PONs (passive optical networks) may be connected simply through the choice of wavelength, using distributed switching and routeing techniques. Extension and evolution of such techniques may enable considerable reduction in the number of switches necessary in a network.Understanding of how best to construct, control, manage and evolve towards a lean, yet future-proofed (ie scaleable), end-to-end broadband national network platform. Strategies for implementing WDM technology in a public telecommunications network.Expected ImpactFlatter and leaner structures for a cost-effective broadband public telecommunications network, through:Upgrade of broadband PON systemsExtensive WDM and wavelength agilitySeamless end-to-end connection of high capacity optical channels across access and core.All-optical distributed switching of all customer connections (single tier)The need for new wavelength standards for fine channel spacings (<100 GHz) is expected.Potential WOTAN test-bed.Main contributions to the programme objectives:Main deliverablesAn end-to-end wavelength agile optical communications system using WDMContribution to the programmeThe technology for a scaleable end-to-end optical broadband networkTechnical ApproachFour major networking concepts will be developed and demonstrated, employing wavelength agility and distributed wavelength routeing and switching, with increasing numbers of wavelength channels:Upgrading broadband PON system by WDMHead-end and switch-node by-pass for high capacity channels (end-to-end all-optical customer channels directly across access and core, eg for LAN-LAN interconnection)Alternative core network structures (comparison of ring, star and mesh)All-optical, end-to-end distributed switching (0.4 nm WDMA/TDMA)Key elements of the project will include:Tunable transmitters and receivers as wavelength-agile modulesWide bandwidth, wavelength-flattened and gain-clamped Yb/Er optical amplifiersGrating-based NxN wavelength multiplexers (passive wavelength-routeing node - PWRN)Variable waveguide attenuator arraysAll-optical wavelength convertersBroadband PON systemOptical cross-connects (3 input and output fibres, 1.6 nm, 16-channel capability)Wavelength referencing sub-systemsCommercial SDH and ATM equipment/layersIntegrated network management platformEnd-to-end networking trialSub-systems in the WOTAN network will be element-managed by the network management system.Summary of TrialThrough the BBC's sponsorship of WOTAN and interaction with internal BT projects, it has been possible to demonstrate an end-to-end high capacity application across BT's London-East Anglian Network (LEANet). This is an advanced, multi-layer transport network test-bed, interconnecting a number of towns and cities in the UK. The demonstration used BBC HDTV equipment and codecs to transmit compressed HDTV and conventional 625 line PAL signals at 270 Mb/s across LEANet into BT Laboratories' VisionDome (supplied by ARC, Raleigh, USA). The VisionDome provides a 180° visual and audio environment for interworking of computer generated and real environments, eg for immersive multimedia environments, video conferencing and shared work spaces.The WOTAN project will culminate in an integrated, end-to-end networking trial, carrying representative customer traffic and services from the "Futures Test-Bed" National Host at BT Laboratories, over LEANet. By making use of the resources of this test-bed and the advanced hardware developed within WOTAN and other ACTS projects (specifically including BLISS), the fibres will be configured as required (subject to operational availability) to demonstrate and test the proposed end-to-end networking principles, sub-systems and technologies. In addition, it is the intention to undertake a joint demonstration of LAN-LAN services and applications with COBNET.Laboratory DemonstratorA laboratory demonstration of an all-optically switched network will also be undertaken. An all-optical, distributed switching sub-system, employing time- and wavelength-agility (WDMA/TDMA) with 0.4 nm channel spacing, will demonstrate the future-proofing capability of optics, to provide very high switched network throughput between customers or terminals on different PONs, without the need for electrical (ATM) switches; a "switchless" network. Elements of the demonstrator will show the potential to operate over a national scale, with closer channel spacings.Key IssuesThe end-to-end nature of the WOTAN project will address:continuous and long-term scalability with traffic demandimpact of customer bandwidth demands and applications on core and access network design and operationcost-effective (lean) network structures and technologiesinterworking issues at the access and core network interfacethe role for an all-optical end-to-end link across the access and core networksthe role for all-optical distributed switchingwavelength channel numbers and spacingsadvanced network, traffic and element managementissues of managing wavelength-agile PON access networks and wavelength-routed core networks within a unified networking environmentinterworking of management platforms for the optical access, optical core and electrical (ATM/SDH) network fabricevolution plans and roll-out strategiescontributions to the international standards debate in the area of wavelength standardisation Champ scientifique engineering and technologyelectrical engineering, electronic engineering, information engineeringinformation engineeringtelecommunicationstelecommunications networksoptical networksnatural sciencesphysical sciencesoptics Programme(s) FP4-ACTS - Specific programme of research, technological development and demonstration in the area of advanced communications technologies and services, 1994-1998 Thème(s) 2 - Photonic technologies Appel à propositions Data not available Régime de financement CSC - Cost-sharing contracts Coordinateur GPT Ltd Contribution de l’UE Aucune donnée Adresse Sopers Lane BH17 7EQ Poole Royaume-Uni Voir sur la carte Coût total Aucune donnée Participants (9) Trier par ordre alphabétique Trier par contribution de l’UE Tout développer Tout réduire BRITISH TELECOM PLC (BT) Royaume-Uni Contribution de l’UE Aucune donnée Adresse Voir sur la carte Coût total Aucune donnée Centro Studi e Laboratori Telecomunicazioni SpA Italie Contribution de l’UE Aucune donnée Adresse Via G. Reiss Romoli, 274 10148 TORINO Voir sur la carte Liens Site web Opens in new window Coût total Aucune donnée ETH-Zurich Suisse Contribution de l’UE Aucune donnée Adresse Voir sur la carte Coût total Aucune donnée GMMT Ltd Royaume-Uni Contribution de l’UE Aucune donnée Adresse Voir sur la carte Coût total Aucune donnée ISA-Jobin Yvon France Contribution de l’UE Aucune donnée Adresse Voir sur la carte Coût total Aucune donnée Italtel Società Italiana Telecomunicazioni SpA Italie Contribution de l’UE Aucune donnée Adresse Castelletto di Settimo Milanese 20019 Milano Voir sur la carte Coût total Aucune donnée Sirti SpA Italie Contribution de l’UE Aucune donnée Adresse Via G.B. Pirelli, 20 20124 Milano Voir sur la carte Coût total Aucune donnée University of Cambridge Royaume-Uni Contribution de l’UE Aucune donnée Adresse Trumpington Street CB2 1PZ Cambridge Voir sur la carte Coût total Aucune donnée University of Essex Royaume-Uni Contribution de l’UE Aucune donnée Adresse Wivenhoe Park CO4 3SQ Colchester Voir sur la carte Liens Site web Opens in new window Coût total Aucune donnée