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Part III. Appendix 2: Data Transport2. The approach leverages hundreds of already-existing, low-level file manipulation utilities. Forexample, utilities such as the NetCDF Operators (“NCO”), which subset, reorder, and appenddata from files immediately, become network tools for performing the same operations on widelydistributed data sets.3. Format independence is achievable through this approach. Applications communicate with filesthrough standardized interfaces (APIs), without knowledge of what occurs behind those interfaces.Format translation may occur without the application being aware of it.The first version of the OPeNDAP core software was released in 1995. There are currently in excessof 40 OPeNDAP sites in NVODS serving more than 300 data sets. A list of data sets accessible isavailable at: http://www.unidata.ucar.edu/cgi-bin/dods/data sets/data sets.cgi?xmlfilename=datasets.xml. In addition to these sites, the NVODS project has forged partnerships with a numberof national and international oceanographic projects (e.g., WOCE/CLIVAR, AOMIP, US GOOS,GODAE, and NOMADS) as requested in the Broad Agency Announcement (BAA) on which theNOPP funding was based.We believe that this recommendation is justified for the following reasons:• The DAP is discipline-neutral. It is based on a small number of data types and organizations ofthese types. This has allowed servers based on the DAP to be built for all data types encounteredthus far in the implementation of the system.• The DAP is in wide use in both research and operational settings.- There are in excess of 40 DAP server installations in the United States, serving well over 300oceanographic and meteorological data sets.- Most of the major ocean data archives are either experimenting with the DAP or use it routinelyfor their data distribution.- In addition to U.S. server installations, there are on the order of 10 installations overseas.- New installations are being added in the United States and oversees at the rate of one or moreevery three weeks.- The DAP has been adopted by the following national and international efforts as the base fortheir data transport needs:• GODAE• NOMADS• AOMIP• ESG II• There is significant experience with the DAP.- The DAP has existed in its current form for approximately seven years.172