Objective The main objectives of the project are to: - Investigate the potential of two means of increasing network efficiency: use of a multi-link protocol such as the string mode; and use of high speed switching.- Design, implement test and evaluate in a realistic environment, a string mode algorithm and a high speed switch.- Design, implement, and test a 34 Mbit/s PDH/ATM Mapper.- Elaborate economically sound introduction strategies.The main objectives of the research were to:investigate the potential of 2 means of increasing network efficiency; the use of a multilink protocol such as the string mode and the use of high speed switching;design, implement, test and evualate in a realistic environment, a string mode algorithm and a high speed switch;design, implement and test a 34 megabits per second PDH asynchronous transfer work (ATM) mapper;elaborate economically sound introduction strategies.The research addressed the following issues:system studies on traffic handling algorithms, aimed at increased network efficiency;experimentation with string mode and high speed ATM switching technologies;technoeconomic evaluations of solutions to meet the early market opportunities with ATM based equipment.The research has resulted in:the issuing of preliminary specifications for network and traffic models;the issuing of a system specification for a 34 megabits per second PDH/ATM mapper, as well as a design specification for a high speed switch;the issuing of a preliminary specification for string mode implementation;the definition of preliminary configurations for string mode and high speed switch demonstrators;the definition of a generic model for the access network which will be used for technoeconomic evaluations in cooperation with other projects.In the network evolution phase towards an asynchronous transmission (ATM) based integrated broadband communications network (IBCN) a strong demand must be expected for services that allow interconnection of physically separate high speed ATM islands. String Mode is a multilink protocol that will meet this need while offering an improvement of network resource utilization in conjunction with statistical multiplexing. The String Mode protocol that distributes a high bit rate ATM connection on parallel physical resources is currently being implemented in a realistic network environment by the use of a 'virtual network' concept that allows a large ATM network to be simulated with limited hardware resources. String Mode is compatible with existing ATM network installations and the results from the implementation work so far indicate that a cost effective implementation is realistic. String Mode can be considered as a pragmatic solution to the problem of interworking between high speed ATM networks through a lower speed intermediate public network, in a transition phase towards a global ATM network.Technical Approach Traffic engineering activities are based on source and node models which have been developed within the project. The performance of string mode algorithms has been evaluated by simulation techniques. To ensure their full integration in the B-ISDN, satellite links have been investigated as a component of the network architecture and an optimised ATM layer protocol devised. A complete demonstrator of the String Mode protocol has been developed allowing simulation of a multi-node ATM network by means of a module which allows multiple passes through a single ATM switch with variable transmission delays on each pass. The project work on high speed ATM switching is based a switch structure which decouples switching speed from the technology employed. It avoids queue access bottle-necks and intensively exploits parallelism and pipe-lining techniques. Implementation is based on a combination of two full custom ASICs, one developed within the STRATOSPHERIC project the other under an ESPRIT project. The physical design is of a 4x4 matrix. The matrix is cascadable, allowing multi-stage configurations. The 34 Mbit/s Mapper has been validated in UNOM (R2023) ATM testbed. Techno-economic studies are performed in close co-operation with other projects, particularly TITAN. Three case studies have been performed to investigate respectively PSTN evolution, CATV evolution and application of String Mode. Key Issues - System studies on traffic handling algorithms, aiming at increased network efficiency.- Experiments with string mode and high speed ATM switching technologies.- Techno-economic evaluations of solutions to meet the early market opportunities with ATM based equipment. Expected Impact The project has demonstrated technical viability of two techniques (High Speed ATM switching and String Mode) which increase network efficiency and hence reduce the cost of the ATM implementation. Cost effective introduction strategies developed by the project will help foster early market opportunities for broadband services. Fields of science engineering and technologymechanical engineeringvehicle engineeringaerospace engineeringsatellite technology Programme(s) FP3-RACE 2 - Specific research and technological development programme (EEC) in the field of communication technologies, 1990-1994 Topic(s) Data not available Call for proposal Data not available Funding Scheme Data not available Coordinator Télécommunication France Address 19 avenue carnot 91348 Massy France See on map EU contribution € 0,00 Participants (12) Sort alphabetically Sort by EU Contribution Expand all Collapse all ANALYSYS LTD United Kingdom EU contribution € 0,00 Address 8-9 jesus lane CB5 8BA Cambridge See on map ARECOM-TELECOM PARIS France EU contribution € 0,00 Address 46 rue barrault 75634 Paris See on map BARCO NV KORTRIJK BELGIUM Belgium EU contribution € 0,00 Address Th sevenslaan 106 8500 Kortrijk See on map British Telecom plc (BT) United Kingdom EU contribution € 0,00 Address British telecom laboratories martlesham heath IP5 7RE Ipswich See on map INTRACOM Greece EU contribution € 0,00 Address 19.5 markopoulou ave 190 02 Peania attika See on map NATIONAL TECHNICAL UNIVERSITY OF ATHENS Greece EU contribution € 0,00 Address Heroon politechniou, zagrafou 157 73 Athens See on map POLITECNICO DI TORINO Italy EU contribution € 0,00 Address Corso duca degli abruzzi, 24 10129 Torino See on map RAYNET Belgium EU contribution € 0,00 Address Diestsesteenweg 692 3200 Kessel-lo See on map REFER NV Belgium EU contribution € 0,00 Address Lange leemstratt 268 B2018 Anterpen See on map SGS-Thomson Microelectronics SrL Italy EU contribution € 0,00 Address Via olivetti 20041 Agrate brianza (mi) See on map TECHNICAL UNIVERSITY OF DENMARK Denmark EU contribution € 0,00 Address Blgd 348 2800 Lyngby See on map TELEFONICA I+D Spain EU contribution € 0,00 Address Emilio vargas, 6 28043 Madrid See on map