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FEP - Format Use by an Archive - NSSDC - CDF
1. Archive Identification
National Space Science Data Center
1.1 Nature of Ingest Activity
NSSDC ingests many data sets via many pathways. Some inflows arrive daily and electronically. Others arrive occasionally, on media. In all cases there is pre-submission interactions between NSSDC and the data provider regarding inflow pathway, schedule, format, etc.
1.2 Nature of User Community
NSSDC has a dual user community - both the space science research community and, for items like planetary images, the "general public." It is intended that data archived at NSSDC should be accompanied by such supporting material as to make the data correctly and independently usable by members of the research community.
1.3 Nature of Archive
NSSDC is both a permanent archive and, in recent NASA/OSS parlance, also an active archive for a subset of its archived data. "Active archive" means providing electronic access and some measure of science expertise in the data.
2. Format (Format System) Identification
Data are archived at NSSDC in a multiplicity of formats. Much long-resident NSSDC data are archived in machine-specific binary datasets. NSSDC uses CDF to underlie the "value added" pathways to its more important space physics data. (CDAWeb, OMNIWeb, etc.) [Note that NSSDC and the Space Physics Data Facility, an NSSDC-peer organization at Goddard, collaborate on these.]
3. Format Selection Rationale
The group that had initially developed CDF for the NASA Climate Data System was reorganized into NSSDC at a time when NSSDC had no other equivalent format standard. NSSDC gradually retuned CDF for space physics.
4. Roles of Format
As of now, CDF functionality is exploited mainly for item 4 - dissemination (in the sense of underlying CDAWeb and like systems).
5. Data Structures Supported
All the indicated data structures are supported by CDF in our CDAWeb-like systems. But CDF is not really exploited yet for the basic archiving function.
6. Support
The CDF development team lives within NSSDC.
7. Software
There is an extensive CDF library of software available from the CDF web page. See the CDF description in the developer's template section of these pages. No software is specifically for baseline archiving.
8. Desired Functions
9. Other Comments
NSSDC has been somewhat reluctant to commit to CDF as the definitive archive format for its data, given its overriding concern for data usability over the long term. If from this process we can be comfortable that the present CDF or some evolved version of it would be truly a long term data standard, we could commit to CDF and then address how we'd exploit CDF functionalities in long term archive management.
Wider Views
Formats Evolution Process (FEP) Discussion Forums PageFormats Evolution Process (FEP) Home Page
NASA/Science Office of Standards and Technology (NOST) Home Page
URL: http://ssdoo.gsfc.nasa.gov/nost/fep/archive-nssdc-cdf.html
A service of
NOST at
NSSDC.
Access statistics for this web are available.
Comments and suggestions are always welcome.
Author: Joseph H. King / NASA/GSFC/NSSDC / (king@nssdca.gsfc.nasa.gov) +1 301-286-7355
Curator: John Garrett (John.Garrett@gsfc.nasa.gov) +1.301.286.3575
NASA Official: Code 633.2 / Don Sawyer (Don.Sawyer@gsfc.nasa.gov) +1.301.286.2748
Last Revised: 1999-10-07 T15:46:32, Joseph H. King