NOST News

Volume 12, Number 2, June 1996
By John Garrett

Development of archiving standards continues to be one of the major activities supported by the NSSDC and the NASA/Science Office of Standards and Technology (NOST). NOST personnel are continuing to spearhead both the international and the U.S. archiving standards efforts by the International Organization for Standardization (ISO) and the Consultative Committee for Space Data Systems (CCSDS). Readers can browse an overview of the U.S. efforts starting at URL http://bolero.gsfc.nasa.gov/nost/isoas/us/overview.html.

ISO Archiving Workshops are the focal point for U.S. efforts. The Third U.S. Workshop was held on March 19-20, 1996, at the National Archives and Records Administration's Archives II facility in College Park, Maryland. Holding the workshop at this state of the art archiving facility served to instill in the participants a sense of the importance and urgency of the tasks before them. The tour of the facility was a reminder of both the diversity of individual archiving methods and the similarity of archive requirements and goals.

The primary focus of this Third U.S. Workshop was to prepare results of the U.S. efforts over the past six months to be submitted to the Second International Workshop held in Pasadena, California, on April 29 and 30, 1996. This workshop was a meeting of the working group contributing to the development of the draft Archiving Reference Model. During the workshop participants discussed a number of scenarios and alternative views related to the reference model. A great deal of work was also done at this meeting to identify and distribute the functions performed by the high level reference model components. Interested individuals can gain access to meeting minutes, the participants list, submitted papers, etc., starting at URL http://bolero.gsfc.nasa.gov/nost/isoas/us03/ws.html.

As the U.S. and International workshops continue, NOST is attempting to capture the understanding gained in the Archiving Reference Model document. The Archive Reference Model serves a variety of purposes. The reference model identifies the high-level abstractions that underlie current archival systems. It defines common terminology and concepts that allow the architectures of existing and future systems to be described and compared. Currently, there are problems in even discussing archives since individuals mean so many different things when they use the word. The reference model will work toward alleviating the problem by clearly identifying various archive functionality and perhaps by identifying various classes or levels of archives based either on functionality or time scales of operations. Thus, the reference model will provide a conceptual and functional framework within which independent teams of experts may proceed with detailed discussions and agreements regarding archiving responsibilities. NOST intends for the ISO Reference Model for Archival Information Services to provide a framework for a series of standards for application and user interfaces to open archival systems.

The current draft has been authored by NOST staff members Louis Reich and Don Sawyer. It is available in Word for Macintosh 5.1 at ftp://nssdc.gsfc.nasa.gov/pub/sfdu/isoas/us03/ref_mod3.m51 or in PostScript at ftp://nssdc.gsfc.nasa.gov/pub/sfdu/isoas/us03/ref_mod3.ps. A new draft will be made available in July 1996. It will include updates from both the Third U.S. Workshop and the Second International Workshop.

NOST is encouraging participation in the U.S. efforts by all interested parties. Levels of participation in the efforts range from simply tracking the efforts toward developing archiving standards to active participation in writing, editing, and reviewing sections of the documents being produced. Regardless of the level of effort readers may wish to devote to these efforts, they may register their interest by filling out the form at http://bolero.gsfc.nasa.gov/nost/isoas/us/registration_form.html. Readers who are unable to access the World Wide Web form can respond by E-mail to Don Sawyer at sawyer@ncf.gsfc.nasa.gov.

The Second International Workshop was held in Pasadena, California, in the closing days of April 1996. That workshop included reports detailing the various national efforts (particularly the U.S. and French efforts) toward developing archiving standards. The workshop also provided a forum for extending the current draft of the Archiving Reference Model. A more detailed description of the conference will be available for the next issue of the NSSDC News. In the meantime, interested readers can access materials from that meeting as they become available at http://bolero.gsfc.nasa.gov/nost/isoas/int02/ws.html.

As mentioned in the previous issue, NOST is actively working with CCSDS to develop recommendations in the data dictionary area. NOST solicited comments from other NASA projects on the CCSDS internal draft of a Data Entity Dictionary Specification Language. Several projects provided feedback that essentially welcomed the current work but asked that it be extended somewhat since current project experience indicates needs beyond the current scope of the document. NOST shared these comments with its international colleagues at the May 1996 CCSDS workshop. Hopefully, CCSDS will be able to extend the document in manners useful in supporting the requirements of current NASA projects. Readers who have a particular interest in data dictionary work can obtain more information or get a copy of the current working draft by contacting Don Sawyer by E-mail at sawyer@ncf.gsfc.nasa.gov.

As one part of its mission, NOST works to codify existing practices. One area where NOST has undertaken this effort is the use of the Flexible Image Transport System (FITS). This work is being conducted in conjunction with the FITS Support Office at GSFC. Information on the FITS format and the FITS Support Office is available through their top level page at http://www.gsfc.nasa.gov/astro/fits/fits_home.html.

The current NOST FITS Definition of FITS, Version 1.1 was approved as a NOST standard in September 1995. It is available on line at http://www.gsfc.nasa.gov/asro/fits/basics_info.html#V1.1. A draft of the NOST Definition of FITS, Version 2 has been completed primarily by NSSDC staff member Barry Schlesinger. The new version incorporates updates such as the IMAGE and BINTABLE extensions, which were subsequently endorsed by the International Astronomical Union FITS Working Group (IAUFWG).

Version 2 is now being reviewed by the NOST FITS Technical Panel. After panel members have reviewed the new draft, the document will be released for review by the public. FITS users should look for its release in the next few months. After comments from the public are addressed by the FITS Technical Panel, Version 2 will be submitted for approval as a NOST standard and then for endorsement by the IAUFWG as the international FITS standard.

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Author:Miranda Beall (beall@nssdca.gsfc.nasa.gov)
Curators: Erin Gardner (gardner@gsfc.nasa.gov) and Miranda Beall (beall@g sfc.nasa.gov)
Responsible Official: Dr. Joseph H. King, Code 633
Last Revised: 21 Nov 1996 [EDG]