HR: 1340h
AN: IN33C-1190 [Abstracts]
TI: NASA`s ECS Data Pool: OGC Compliant Web Services for Every User and Every Pocket
AU: * Bories, C
EM: cristina_bories@raytheon.com
AF: Raytheon RIS, 1616 McCormick Dr., Upper Marlbolro, MD 20774
United States
AU: Marley, S R
EM: stephen_r_marley@raytheon.com
AF: Raytheon RIS, 1616 McCormick Dr., Upper Marlbolro, MD 20774
United States
AB:
The NASA Earth Observing System (EOS), supports operations for several satellites including Landsat 7, Terra, and Aqua. ECS
(EOSDIS Core System) is a vast archival and distribution system and includes several Distributed Active Archive Centers
(DAACs) located around the United States whose combined holdings now exceed 3.5 petabytes, with a daily distribution of
3.5TB.
In response to evolutionary changes in technology, the user access services have been moving a substantial part of its
distribution capability away from distribution from near-line tape archives to large on-line disk caches that hold several
10's of terabytes of high-value data that allow users to obtain products via electronic download using a web
or ftp clients.
Although these basic access services are valuable, the need for more advanced services such as data reformatting and
subsetting was seen as key to the interoperability and broader adoption of NASA's data with current Decision
Support and Geographical Information Systems. Therefore, in 2003, Raytheon was funded to initiate the development of an
in-house demonstration prototype that integrated OGC web services (Mapping and Coverage) with reformatting capability
(HDF-EOS to GeoTIFF).
The experience obtained from that first prototype, led to the formulation of a generalized interoperable architecture, which
incorporated a catalog service.
Two operational prototypes are now deployed for NASA. The first, utilizing IONIC Software's OGC services is
designed to serve large data volumes (up to 50000 pieces of inventory of 10 MODIS data types), and to offer faster access
performance. The second prototype was developed from a combination of open-source web services, freeware, and hosted in
commodity platforms (Linux based PCs), and had as a main objective to provide a low entry cost services, for potential new
data providers. For example, a small University research team, which could find difficult to afford the elevated cost of COTS
licenses or powerful workstations that a DAAC has access to. Both prototypes were integrated with the reformatting tool and
with several OGC compliant clients.
The Catalog service was implemented by developing an OGC facade over the existing ECHO metadata clearing house. This
facade allows ECHO to be registered as an NSDI node, and make Data Pool web services and data discoverable through
Z39.50 catalog searches.
Both prototypes are currently in test and evaluation at the respective Data Centers and will be formally benchmarked early
2006 to characterize usage and performance.
DE: 0530 Data presentation and visualization
DE: 1694 Instruments and techniques
DE: 3360 Remote sensing
SC: Earth and Space Science Informatics [IN]
MN: Fall Meeting 2005