PILOT SYSTEM ARCHITECTURE
THE CRO.CU.S. SYSTEM COMMUNICATION
The CRO.CU.S communication system operates on a satellite platform based on the Digital Video Broadcasting (DVB) standard world-wide deployed for the digital television an IP high speed data with the same small antenna. The main components of the communication system, implemented by Telespazio to run the CRO.CU.S services, are:
·    -       the Telespazio Service Centre: where are located the system equipment and the distance learning NetStre@m platform.
·     -      the Up-link station: located at FUCINO (AV) Space Centre
·     -      the Space Segment: to roll out the CRO.CU.S pilots, a 512 kbps Ku band on the Eutelsat 13°East Hot Bird fleet is used.
·     -      a teacher station: this remote station allows the COSPE Centre in Florence to manage the telekiosk services and to schedule the contents distribution.
·    -       a satellite network: including the CRO.CU.S Pilot Schools and the Project Partners.
 
Fig.1 CRO.CU.S System Architecture
CRO.CU.S  Services Satellite Coverage
Thanks to Eutelsat 13° E  Hot Bird fleet the satellite coverage guarantees to reach every country of West and East Europe plus those countries who belong to the Mediterranean Sea basin so including all those areas greatly affected by the immigration phenomena.  
 
 
   Fig.2 Satellite Coverage
 
 
CRO.CU.S Satellite Network
During the pilot phase, the CRO.CU.S Satellite Network  includes 30 Italian Schools located in Lombardy, Venetia, Tuscany, Emilia Romagna, Latium, Basilicata and the Partners: Cospe, Silab, Shkoder University in Albania , the University for Foreign People of Siena and Telespazio.  
 
 
Fig.3 CRO.CU.S Network
 
The communication among users and the Service Centre is performed in a asymmetric way: the users receive the multimedia data via satellite at high rate and transmit via modem their data at the rate allowed by their terrestrial Internet connection.
The multimedia contents, as language courses, are sent (FTP) to the Service Centre by the Partners Content Providers.
Cospe manages, by mean of the “teacher” remote station, connected to the Service Centre with a 128 kbps link, “live “ services and the schedule of the courses to be transmitted.
The students receive the learning programs via satellite and, by the Internet terrestrial connection, access to the CRO.CU.S  satellite Portal where are located all the multimedia contents. Through this Portal, it is possible interact with COSPE during the satellite session of Tele-Kiosk .
 
User Station
The Schools are equipped within an user station including a PC, configured with a DVB board, a modem analogue or ISDN ( according to the local Internet connection), and a satellite antenna (diameter about 80 cm). In some cases the receiving satellite system has been connected to the School LAN.  
 
 
 
Fig.4 User Station configuration
 
Delivery modalities of CRO.CU.S Services
The users: students, teachers of families can enjoy the CRO.CU.S services related to the information (tele-kiosk) and to the learning ( language and intercultural courses) or in real time or at the time of their convenience.
The CRO.CU.S services are configured and delivered in a  “interactive” or “push” modality according their typology  or the need to interact.  
 
 
Fig.5 Delivery modalities of CRO.CU.S Services
 
Interactivity modality
The NetStre@m satellite platform is operating in delivering “live” services, as learning or tele-kiosk sessions. The teacher or tutor, from the “teacher“ station of COSPE, are visualised on a particular layout that, also, allows to manage the audio and text communication with the audience and to interactively collaborate on documents and images showed on the “white board area”. The user can participate to the “LIVE” sessions at the time when they are scheduled.  
 
 
Fig.6 NetStre@m Layout
 
Push modality
This modality of delivering services uses the “package delivery” functionality, that allows to distribute by satellite to the user stations scheduled intercultural and language courses.
The programs delivered by satellite can be accessed by the home page without the link to Internet. This connection, instead, will be automatically activated towards the Control Centre of SiLab to exploit the exercises.  
 
Fig.7 CRO.CU.S Home Page