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Part III. Appendix 2: Data Transportity and workloads of clients while avoiding as much as possible the need for a mediating, formattranslatingserver. In general, servers would assume the responsibility for translating archived datainto agreed-upon configurations.OGC/OGIS/BMS has concentrated on designing and implementing specialized mediating servers,and the datatypes it has used to date tend to be restrictive, compared to the needs of IOOS.DEI’s FSDM provides an interesting contrast to OPeNDAP. The separation of location information(under the Mesh object) from variable values (under the Data object) is: (1) unlike OPeNDAP’sGrid datatype, which contains a sequence of locations followed by the variable values, but (2) reminiscentof OPeNDAP’s separation of data values (the DataDDS), grammar instance (the DDS), andgrammar-instance-structured metadata (the DAS). Perhaps the thinking that has gone into the designof FSDM can inform an effort to integrate metadata more gracefully into IOOS’s system thanOPeNDAP does at present, particularly metadata applicable to a data set as a whole. Conversely, theOPeNDAP grammar may suggest ways to extend FSDM’s capabilities well beyond its current restrictivegeospatial (location-keyed) data.Syntactically consistent delivery of equivalent dataIn OPeNDAP, one can imagine syntactic uniformity being imposed upon equivalent informationby a software module inserted at each server between the module that extracts archival datato its closest OPeNDAP DDS-grammar representation and the module that transmits the DDS/DataDDS/DAS family. This interposed module would be capable of examining a DDS and recognizingwhether it was an instance that could be re-expressed in a conventionally agreed upon, informationallyequivalent form, and then performing the transformation. The problem of designingsuch a module could be made easier by first ascertaining whether, as seems likely, most requests arefor such simple data structures as arrays involving one or two variables in four-dimensional spacetimeand then concentrating on recognizing such cases.DEI’s FSDM should be examined to see whether it has dealt with the issue of reorganizing the syntacticstructure of data.181