Transcript Integrated Global Data Dissemination Service (IGDDS) IGDDS – Main Goal • “Ensure the definition and operational implementation of an efficient circulation scheme of.

Integrated Global Data Dissemination Service
(IGDDS)
IGDDS – Main Goal
• “Ensure the definition and operational implementation of
an efficient circulation scheme of space-based
observation data and products meeting the needs of
WMO programmes, and in the context of the WIS”
IGDDS – Functional Scope and Focus
• Main functions:
– Data concentration and inter-regional data exchange
– Data dissemination (predominantly via telecom satellite direct
broadcast) with quasi-global coverage
– Data access on request (allowing data discovery and delivery to
authorised users)
– Data and user management including interoperable catalogue,
quality of service monitoring and user support
• Focus on real-time aspects (time-critical data)
IGDDS – Dissemination Requirements
• All Continents in all WMO Regions to be covered by the IGDDS
(possibly using a combination of dissemination mechanisms)
• Data from multiple observing systems to be disseminated in an
integrated manner
• Reception terminals to be openly available at an affordable price
• Data to be disseminated in internationally agreed formats
• Data-handling priority scheme to ensure optimal timeliness
• Operational nature (reliable and continuous)
• …….
Conceptual Architecture
IGDDS within WIS in each region
IGDDS
components
All WMO programmes
data & products (mostly non-satellite)
Data Collection &
Data Collection or
National
Data from
Product Centres
Other regional
Product Centres
Centres
operational Polar
data:
and Geostationary
R&D, high-level
satellites available
products
within region
Inter-operability
Inter-regional
Global Information
Data Collection
System Centre
or Product Centre
and data exchange
(For Met. Satellite products)
data
exchange
Other data
communication
means
Data Dissemination (via telecom satellite)
footprint #1
User
Community #1
Other datacommunication
means
footprint #2
User
Community #2
Users
IGDDS – Satellite Dissemination Physical Architecture
• Currently the IGDDS Satellite Telecommunications
physical architecture consists of
Region
Europe
Africa
South America
North and Central
America
Asia-Pacific
Service
EUMETCast Ku-Band Europe
EUMETCast C-Band Americas
EUMETCast C-Band Americas
EUMETCast C-band Americas
Uplink Hub
Usingen
Usingen
Usingen
Usingen
FengYunCast C-Band
China
• In addition Roshydromet operates the MITRA system
which covers the whole of Europe and a significant part
to Asia
IGDDS – Satellite Dissemination Coverage Footprints
EUMETCast
HB-6, AB-3, NSS806
FengyunCast
Americas Notional Coverage
(Asiasat-4)
IGDDS – Satellite Dissemination Technical Features
•
Significant part of the dissemination network currently provided by
EUMETCast:
– Generic, multi-service dissemination system based on standard Digital Video
Broadcast (DVB) technology
– Commercial broadcast channels on TV, DTH telecommunication satellites
– Off-the shelf, commercially available, reception equipment
– IP over DVB standard coding
– Transparent transfer of files, i.e. files received exactly as sent
– Use of standard formats - XRIT, BUFR, GRIB, HDF
– Secure access control at individual file and User level
– Open, flexible, scalable architecture
– Availability better than 99.5%
– Near real-time with guaranteed timeliness
– Suitable for any file-based datastream
• FengyunCast system very similar in concept to EUMETCast – main
difference is in the multi-cast software
IGDDS – EUMETCast Dissemination Dataflows
IGDDS - Implementation Issues
• Implementation mechanisms used include:
– IGDDS Implementation Plan
– IGDDS Implementation Group
• Successor to the IGDDS Workshops
• First meeting of IG: July 2007 in Geneva
• 1st Meeting of Implementation Group identified 5 priority
actions/challenges
– Identification of data requirements in each region
– Quasi-global dissemination coverage on a sustainable basis
– Identification of suitable data exchange mechanisms for transferring data
between regions
– Provision of appropriate user support arrangements
– Robustness
IGDDS - Priority Actions and Challenges (1)
• Identification of regional data requirements
– For Europe and Africa the data requirements are relatively welldeveloped, and reflected in the relevant EUMETCast dissemination
schedules
– For the Americas and the Asia-Pacific regions this is not the case, and
actions are underway to collect/consolidate the requirements
• Outputs are expected for the A-P region, following the APSDEU-8 meeting
• Roshydromet will provide sub-regional requirements at the next IG meeting
• CMA will indicate the current FengYunCast dissemination content and A-P
partners will propose additions for consideration by CMA
– Focus of the IGDDS IG is on
• ensuring that appropriate mechanisms are in place for gathering
requirements (with an emphasis on real-time aspects)
• Adoption of a harmonised format for the requirements
IGDDS - Priority Actions and Challenges (2)
• Quasi-global dissemination coverage on a sustainable basis
– For Europe and Africa the current status is satisfactory (with the
EUMETCast Ku-Band Europe and EUMETCast C-Band Africa services)
– The Americas are currently served by the EUMETCast C-Band Americas
service (apart from a gap over N-W America). However this service is
not assured beyond 2008
– A NOAA service is in preparation but only in the framework of
GEONETCast
• it is not planned to carry image data on the new NOAA service
• It is assumed by NOAA that their new service will coexist in parallel to the
EUMETCast C-Band Americas service
– The FengYunCast service, and its extension to the Asia-Pacific region, is
currently the subject of a pilot activity
IGDDS - Priority Actions and Challenges (3)
• Identification of suitable data exchange mechanisms for
transferring data between regions
– For the foreseeable future it is anticipated that a combination of
the following mechanisms will be used:
• Dedicated links
• GTS and extensions thereof
• Internet
• Overlapping dissemination footprints
– Situation is still embryonic
• Uncertainty about number of regional hubs (3 or 4) – could affect the
data exchange network architecture
• Unclear situation regarding the data that needs to be exchanged
(linked to identification of regional data requirements)
IGDDS - Priority Actions and Challenges (4)
• Provision of appropriate user support arrangements
– The Asia-Pacific user community with a number of different
languages in use within the region
– The extension of the Chinese national FengYunCast system to
the full Asia-Pacific region requires the establishment of
appropriate user support arrangements
– ABoM is assisting as a pilot user in the A-P region and this pilot
activity is expected to identify the main user support areas which
need further development
IGDDS - Priority Actions and Challenges (5)
• Robustness
– Integrating many data flows within a limited number of
dissemination services results in the increased exposure to single
point failures
– With this increased concentration strategic redundancy (as
opposed to the redundancy required to meet operational
availability performance figures) becomes increasingly important
to ensure long-term data continuity
– IGDDS standards will aim to ensure that “strategic redundancy” is
addressed at appropriate levels taking advantage of both the
ground and space-based telecommunications capabilities and of
the interconnectivity between DCPCs and GISCs
Compliance with Applicable WIS Standards
• Following a presentation of the Status of the WIS development at the
IGDDS Implementation Group meeting, there was discussion as to
the standards that were of particular relevance to the IGDDS
• It was concluded that the main items of relevance to the IGDDS
were:
– The WIS filenaming convention
– The WIS Core Metadata Profile standards
• It was noted that EUMETCast carries multiple data sources with
different applicable standards, with filenames often used as a source
of high-level metadata (with the more detailed metadata embedded
in the actual data file).
• To better understand the implications of compliance, EUMETSAT
undertook to investigate the implications of applying this convention
and standards to a relevant test case (ATOVS data was suggested)
with a due date of mid-November 2007
IGDDS and GEONETCast
• GEONETCast could be simplistically viewed as the extrapolation of
the IGDDS satellite dissemination functions to include data from the
GEO Societal Benefit Areas (SBAs)
• With the notable exception of the Americas, GEONETCast generally
makes use of the same basic dissemination infrastructure as the
IGDDS and often simply involves the purchase of additional
bandwidth to include data from other SBAs
• For the Americas, the current planning means that GEONETCast
and the IGDDS could become decoupled
– The EUMETCast C-Band Americas service will continue to provide the
IGDDS component (at least up to 2008)
– The planned NOAA GEONETCast Americas service will provide the
GEONETCast component (planned for the 2nd half of 2007)
IGDDS – Satellite Dissemination Coverage Footprints
EUMETCast
HB-6, AB-3, NSS806
FengyunCast
Americas Notional Coverage
(Asiasat-4)