Objectif Summary of objectivesCarrying out research in the area of integration of terrestrial closed and public networks by transparent and future intelligent satellites (with on-board switching and processing), taking into account the relevant earth segment. Study of problems of internetworking between heterogeneous networks, protocol aspects, network management and control, traffic management techniques and strategies for network evolution.Study of new transmission and satellite access techniques making efficient use of the satellite capacity.Definition of suitable gateways between terrestrial and satellite networks, especially for the integration of LANs and ISDN networks by satellite.Elaboration of a pilot system for integrating terrestrial and satellite networks supporting mixed-media traffic (data, voice, video) and harmonisation with future terrestrial networks and the relevant techniques (e.g. ATM switching). Demonstration of the advantages of satellites, particularly in areas with a poor telecommunications infrastructure. Current statusCOST 226 finished its work with the final symposium in Budapest in May 1995. The results of the work are summarised as follows : A comprehensive systems definition study for LAN interconnection by satellite, covering the areas of user requirements, protocol issues, local and wide area terrestrial and satellite networks, commercial aspects (e.g. competing systems and tariffs) was carried out. The user requirements study showed that the most important applications are file transfer, data base access and E- mail. Integrated voice and videoconference services are becoming increasingly important. These are applications which can be well supported by satellite systems. Traffic measurements and analyses revealed the chaotic behaviour of LAN traffic. Multiplexing of different LAN traffic does not improve the situation. This has to be taken into account when designing the demand assignment access scheme. Since the survey showed that the most widely used protocol is TCP/IP, detailed measurements of the performance of TCP/IP on real and simulated satellite links were carried out followed by a thorough analysis of the results. By optimisation of the protocol parameters (window and buffer size) good throughput can be achieved. Performance measurements were also carried out on a VSAT network in Spain ; these line up well with the theoretical investigations and simulations. Reference models for LAN and ISDN interconnection by satellite were elaborated using formal description techniques. Case studies were conducted. A novel TDMA transmission scheme stemming from the work in the area of on-board processing satellites was elaborated, operating on a symbol-synchronous basis. It minimises the overhead for synchronisation, normally necessary in conventional TDMA systems. Furthermore this new system can operate at low signal to noise ratios and is hence beneficial for satellite systems using small and inexpensive earth stations. The design of a novel satellite gateway based on TDMA was completed and a prototype developed. Based on transputers which provide real parallel processing, it makes use of ATM cell switching and can be immediately interfaced to existing protocol routers or network hubs, providing interoperability between heterogeneous networks. Several access schemes were studied in detail. The development of the FODA-IBEA access scheme, done in Italy, showed that the satellite link can be divided efficiently among many users (stream and datagram applications are mixed, reservation is based on different types of traffic). Demonstration systems were set up, initially using existing facilities in the various laboratories. At the COST 226 workshop in Graz in 1993 three sites (Graz, Oberpfaffenhofen and Budapest) were interconnected via the OLYMPUS satellite using an experimental TDMA controller. LAN traffic and digital video and audio was supported at data rates of 2 Mbit/s. A tele-seminar applications was successfully shown : all presentations of the workshop were broadcast to the other sites, from where participants could ask questions to the referees via the return link. Access to remote image data bases via satellite was demonstrated as a LAN application. Researchers were using multi-media workstations for the display of the remote sensing images. Using in-window videoconferencing the specialists could interactively discuss the results. At the Final Symposium a demonstration of the satellite gateway was made showing remote access to the Internet at high speed and simultaneous video conferencing.% Work plannedThe MC of COST 226 elaborated the MoU for a follow-on Action, COST 253, dealing with integration of networks by low-orbiting satellites. This Action started in October 1996. Programme(s) IC-COST - European cooperation in the field of scientific and technical research (COST), 1971- Thème(s) 1 - Telecommunications Appel à propositions Data not available Régime de financement Data not available Coordinateur Technical University Graz Contribution de l’UE Aucune donnée Adresse Inffeldgasse 12 8010 Graz Autriche Voir sur la carte Coût total Aucune donnée Participants (15) Trier par ordre alphabétique Trier par contribution de l’UE Tout développer Tout réduire Diensten Programmatie Wetenschapsbeleid Belgique Contribution de l’UE Aucune donnée Adresse Wetenschapsstraat 8 1040 Bruxelles Voir sur la carte Coût total Aucune donnée Elektroteknicki fakultet Croatie Contribution de l’UE Aucune donnée Adresse Zagreb Voir sur la carte Coût total Aucune donnée European Space Agency (ESA) Pays-Bas Contribution de l’UE Aucune donnée Adresse Keplerlaan 1 2200 AG Noordwijk Voir sur la carte Coût total Aucune donnée HAS Central Research Inst. for Physics Hongrie Contribution de l’UE Aucune donnée Adresse Konkoly Thege u 29-33 1525 Budapest Voir sur la carte Coût total Aucune donnée Jutland Telephone Danemark Contribution de l’UE Aucune donnée Adresse Sletvej 30 8310 Tranbjerg Voir sur la carte Coût total Aucune donnée NEWTEC CY Belgique Contribution de l’UE Aucune donnée Adresse Mechelsesteenweg 27 2018 Antwerp Voir sur la carte Coût total Aucune donnée Regie des Telegraphes et Telephones Belgique Contribution de l’UE Aucune donnée Adresse Rue des Palais 42 1210 Bruxelles Voir sur la carte Coût total Aucune donnée SAIT sa/nv Belgique Contribution de l’UE Aucune donnée Adresse Chaussee de Ruisbroek 66 1190 Bruxelles Voir sur la carte Coût total Aucune donnée Selenia Spazio SpA Italie Contribution de l’UE Aucune donnée Adresse Via Saccomuro 24 00131 Roma Voir sur la carte Coût total Aucune donnée Societá Italiana per l'Esercizio delle Telecomunicazioni SpA Italie Contribution de l’UE Aucune donnée Adresse via di val Cannuta 250 00166 Roma Voir sur la carte Coût total Aucune donnée Swedish Telecom Radio Suède Contribution de l’UE Aucune donnée Adresse Rudsjoeterrassen 2 13680 Haninge Voir sur la carte Coût total Aucune donnée TELESPAZIO SPA Italie Contribution de l’UE Aucune donnée Adresse Via Tiburtina 965 ROMA Voir sur la carte Liens Site web Opens in new window Coût total Aucune donnée Tecnopolis CSATA Italie Contribution de l’UE Aucune donnée Adresse Strada Provinciale per Casamassima Km 3.00 70010 Valenzano (Bari) Voir sur la carte Coût total Aucune donnée Telefonica Investigacion y Desarrollo Espagne Contribution de l’UE Aucune donnée Adresse c/ Emilio Vargas 4-6 28043 Madrid Voir sur la carte Coût total Aucune donnée University of Zagreb Croatie Contribution de l’UE Aucune donnée Adresse Unska 3 41000 Zagreb Voir sur la carte Coût total Aucune donnée