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EUMETCast EUMETSAT’s Broadcast System for Environmental Data. Concept & Overview. Generic, multi-mission dissemination system based on the standard DVB multicast technology Use of commercial telecommunication satellites Allowing use of off-the shelf, commercial, inexpensive equipment
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Concept & Overview • Generic, multi-mission dissemination system based on the standard DVB multicast technology • Use of commercial telecommunication satellites • Allowing use of off-the shelf, commercial, inexpensive equipment • DVB/MPEG-2 based transport for carrying IP datagrams • Use of a set of broadcast satellite forward channels (no return channel) • Components: • Data providers • Service management provider (EUMETSAT) • Uplink service provider • Turn around service provider(s) • Satellites • (Reference) Reception stations
Components • Data Providers • Provide, via FTP over a number of communication lines (Internet, VPN, leased lines, …), the files to be disseminated, currently: • EUMETSAT • DWD (Germany) • OSI SAF (Norway & France) • VITO (Belgium, Vegetation Products) • Service Management Provider (EUMETSAT) • Performs all service configuration (bandwidth, users, encryption parameters, dissemination parameters, …) to the DVB uplink provider via FTP over a secure communication line
Data Providers & Service Management Provider Data DVB BROADCAST Service Management Other Sources DWD EUMETSAT DVB UPLINK USERS SAFs
Components • Turn around Service Provider(s) • Receives the DVB signal provided by the uplink service provider • Retransmits the data (on DVB packet level) to another S/C • Receives retransmitted data by a local reference reception station for service monitoring and service level agreement tracking • One turn around service implemented for African Users (not covered by the uplink service) • Current contract with Telespazio • Turn around station in Fucino/Italy
Components • Satellites • Commercial digital TV geostationary satellites for data reception and transmission • Uplink service S/C: • Hotbird-6 • Located at 13 degree East • Ku-Band transponder used • Turn around service S/C: • Atlantic Bird-3 • Located at 5 degree West • C-Band transponder used
Components • (Reference) Reception Stations • Same equipment for different purpose • Reference reception stations for monitoring of the health of the system and for service level agreement tracking • Reception stations for the end users • Consisting of antenna/feed/LNB, DVB receiver card, Workstation & S/W • Antenna: • Size (diameter) depending on EIRP figure at location (=> table) • LNB: • For Ku-band: standard digital TV LNB • For C-band: different brands, proposed by service provider and used at EUMETSAT: California Amplifier 140105-1
Components • DVB Receiver Cards used at EUMETSAT • TechniSat SkyStar2 • BroadLogic V@box 2030 • Pentamedia Pent@value • Workstations • Standard / state-of-the-art PC (with USB port) • Software • Operating Systems: Windows suite & LINUX • EUMETCast Client Software: tq®-TELLICAST • Supporting processing, monitoring & logging of incoming data • Configuration constraints: • Recommended/tested combinations: Ku/C-band <=> DVB receiver card <=> Operating System
EIRP to Dish Size Conversion Table (indicative) EIRP, dBW Dish, cm 51 60 50 67 49 75 48 85 47 95 45 120 42 160 40 200 39 240 37 300 Components
Components: Parts and Costs of a Reception Station DVB Standard Hardware LNB Ku-/C-band & Satellite Dish 200/1000 EUR DVB PCI Card 100 EUR DVB Multicast Client software 60 EUR EUMETCast key unit (EKU) 40 EUR PC, Hard disk, Ethernet 800 EUR 1.200/2000 EUR
C-band Reception Issues • 2.4 m antenna dish recommended for Africa & Europe (3.0 to 3.7 m for some African/Indian Ocean islands) • 1.8 m dish in many cases sufficient (depending also on the quality (noise temperature) of the LNB • C-band significantly less susceptible than Ku-band to rain attenuation, but suffering frequently from electromagnetic interference (mainly radar) • Implementation of bandpass filters has shown good results => elimination of (nearly) all interferences
Current Services • High Rate SEVIRI Image Data - data from Meteosat-8 • Low Rate SEVIRI Image Data - data from Meteosat-8 • Rapid Scanning Service (RSS) - data from Meteosat-6 • High Resolution Image (HRI) - data from Meteosat-7 • Indian Ocean Data Coverage (IODC) - data from Meteosat-5 • Data Collection and Retransmission (DCP) • Meteorological Data Dissemination (MDD) • Meteorological Products (including Satellite Application Facility products) • EUMETSAT ATOVS Retransmission Service (EARS) • Foreign Satellite Data (FSD) • DWDSAT
Service Monitoring • Each data provider is responsible for the monitoring of its own data • EUMETSAT monitors the end to end service for the data provided by EUMETSAT • Each service provider (uplink service and turnaround services) is responsible for monitoring its complete service (penalties in case of failing to accomplish the service level agreement)
Encryption • Enables independent targeting of files towards a single user or group of users • Enables secure control of access at individual file & user level • Encryption in accordance with EUMETSAT’s data policy • Using the tq-tellicast server S/W • Based on the Blowfish algorithm (symmetric 128 bit data keys) • Performed in the EUMETCast uplink server • Data keys valid for just one transmission • Data keys encrypted with private key of target user • On the fly encryption, can be switched off on a per channel basis
Decryption • Decryption by the tq-tellicast client S/W in combination with a decryption device (EUMETCast Key Unit: EKU) and the EKU S/W package • EKU is an USB device • EKU in conjunction with corresponding username and user_key/password enables decryption of licensed services • Only data described as “essential” are decrypted without EKU • EKUs are distributed by EUMETSAT to registered users
EUMETCast Licensed & Essential Services • Licensed Services • Subject to a Licensing Procedure • Involving Secretariat and National Met Services • Comprising forms, tellicast S/W and EKUs • Essential Services • No licensing, but registration by the Secretariat • Provision of tellicast S/W & generic username/password • EKU not required
User Registration • Steps for Access to the EUMETCast Services: • Complete the EUMETCast Registration Form, indicating the requested services • If access to licensed service(s) requested, EUMETSAT’s User Service Helpdesk will forward your Registration Form to the relevant Licensing Agent (generally the National Met Service) • Once licensing procedure completed (and bill paid for EUMETCast Client S/W & EKU): • Access granted (by encryption configuration) • Reception of EUMETCast Client S/W • Reception of username and user_key/password • Reception of EKU (if required)
EUMETCast Service Availability • EURD figure (complete & timely Repeat Cycles): 95% • MOSS figure (complete & timely Repeat Cycles): 99% • Service Level Agreement (SLA) with both service providers (T-Systems and TELESPAZIO): 99.50% • Ku-band Performance (following graph): • T-Systems HRIT segment figures only, comprising performance of uplink system, Hotbird-6 and reference reception station • C-band Performance (following graph): • TELESPAZIO HRIT segments figures only, comprising perf. of turn-around system, Atlantic Bird-3 and ref. reception station • Total Performance (following graph): • Percentage of complete and timely received Repeat Cycles, covering all non-availabilities (Ground Segment & Service Prov.)
EUMETCast Service Extensions Envisaged • Evolution of Meteosat-8 meteorological products • New products based on prototyping by MET (Clear sky Reflectance Map product (CRM) being the next one) • Updates of existing products based on operational experience • VEGETATION derived products for Africa • VEGETATION products from the VEGETATION instrument on SPOT • Operational trial phase has started, dissemination of 10 day Vegetation Index product (S10NDVI) to Users in Africa • EUMETCast/EPS Convergence • EPS global products to be disseminated using EUMETCast; • Initially, this focuses on level 1 and 2 global products generated in the CGS at EUM; • Global level 1 and 2 PDUs per instrument will be available as a EUMETCast service; • Will be extended to SAF products as appropriate.
EUMETCast Service Extensions Envisaged • EUMETCast coverage extension to South America • implementation of a turn-around system – similar to that provided by TELESPAZIO for Africa => under discussion with member states • Basic meteorological Data from WMO regional Association VI • RA VI is Europe and Middle East • Use of EUMETCast for basic provision of observations and forecasts • Working Group under RA VI is establishing user requirements • Formal proposal to EUMETSAT delegate bodies presented • Extension of DWDSAT service planned by DWD (Spring 2005)