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Toward A National Research Network Appendix B: Ocean Science Community Network Requirements (Electronic Bulletin Board Message) Overview Overall scientific goals and objectives The ocean science community is broad: the disciplines of physics, biology, chemistry, and geology are represented. Field research programs may have a global scale. Ocean modelling is done using supercomputers at a number of centers. Oceanographic datasets tend to be large but inhomogeneous and disaggregated. With the increasing use of satellites for research purposes, there will likely be an order-of-magnitude increase in the size of the datasets. Correspondingly, there will likely be an increase in the homogeneity of the datasets. A number of major coordinated global oceanographic experiments are planned to take place over the next decade. Most of them are directed to understanding fundamental problems related to global climate and its prediction. In many cases, the line between ocean and atmospheric sciences is not well defined. TOGA Tropical Ocean Global Atmosphere WOCE World Ocean Circulation Experiment GOFS Global Ocean Flux Study PIPOR Program for International Polar Research GSP Greenland Sea Project Regional and process studies The above programs are linked to satellite sensors that are planned or proposed in support of these and other programs: ocean currents altimeter GEOSAT ocean currents altimeter TOPEX/Poseidon(NASA/CNES) ocean currents altimeter ERS-1 (Europe) wind stress scatterometer NROSS wind stress scatterometer ERS-1 (Europe) SST, feature tracking AVHRR NOAA SS, feature tracking radiometer MOS-1 (Japan)
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Toward A National Research Network ocean color CZCS Nimbus-7 ocean color SeaWiFS Landsat-6 sea ice SAR ERS-1 (Europe) sea ice SAR JERS-1 (Japan) sea ice SSM/I DMSP These global ocean science programs have present needs for worldwide computer networking capabilities that will grow as they enter their implementation phases. In the longer term, the ocean science component of the Global Change program will have a worldwide scope that will present an enormous challenge in its needs for coordination, computation, and data management. The program will thus have a correspondingly great need for computer networking. Typical Ocean Sciences program resources (e.g., observatories, catalogues, archives, supercomputers, international data, other facilities, etc.) US Data Centers National Data Centers National Oceanographic Data Center (NODC) NASA Ocean Data System (NODS) National Climatic Data Center (NCDC) National Center for Atmospheric Research (NCAR) National Snow and Ice Data Center (NSIDC) National Space Science Data Center (NSSDC) National Geophysical Data Center (NGDC) Specialized US Program Data Centers TOGA/WOCE thermal data center, Scripps Institution Sea-Level Data Center, University of Hawaii Alaskan SAR Facility, University of Alaska World Data Centers WDC-A, Oceanography, Washington, DC Meteorology, Asheville, NC Geophysics, Boulder, CO WDC-B, Oceanography, Meteorology, Geophysics, Moscow International Program Data Centers (partial list) TOGA Subsurface Data Center, Brest, France WOCE Hydrographic Program Data Center,? ERS-1 Data Centers, Frascati, Toulouse, Brest,…
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Toward A National Research Network TOPEX Data Centers, Pasadena, Toulouse, Brest,… Permanent Service for Mean Sea Level, Bidston, UK Ocean Drafters Data Center, Ottawa, Canada Academic Sites (partial list) University of Miami University of Rhode Island University of Wisconsin University California SPAN Ocean Network Information Center (SONIC) at the University of Delaware College of Marine Studies. Functions as ocean community network center. NODS is developing a Global On-Line Director (GOLD) to function as an ocean community distributed catalog. Other catalogs are in existence or being developed at the national data centers and some of the specialized data centers. Nearly all the developing catalog systems assume a networked distributed access. Supercomputer centers at NCAR and elsewhere are used extensively for ocean modeling. Many US oceanographic centers are linked by the University Satellite Network (USAN) which provides medium speed (56 kbps—223 kbps) access to the supercomputers at NCAR. Additionally, about 20 oceanographic institutions are on regional nets having network affiliations with NSFNET. Ocean-going research vessels are connected via ATS communications satellite (ground station located at the University of Miami) and thence onto a network (SPAN). There is thus the possibility of networking data from ships anywhere in world to analysis centers. Island stations and deep-sea moorings collect and often telemeter data in real time. These instruments are often in harsh environments with problems (of saltwater corrosion and thousands of atmospheres of pressure) that are frequently more difficult than those in the space environment. . Characterization of data needs (e.g. image transfer (and sizes), interactive remote process control, instrument control, normal interactive access, mail, video conferencing, expected future growth) File transfer needs High-resolution digital imagery from satellites – volume large ocean charts & sections – volume moderate datasets – volume moderate to large text – volume small to moderate
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Toward A National Research Network Data compression techniques are currently employed for transmission of satellite imagery. In such situations, the transmission is critically dependent upon a low bit-error rate, so that error-correcting routines are generally applied, thereby lowering the effective transmission rate. Large dataset transfers may be done by mailing tapes rather than over a network. Remote process control is down the line and is not yet commonplace in the ocean sciences. At-sea data telemetry is sometime used. Interactive computer access will be used for searching and obtaining datasets. Mail is, of course, already extensively used for program coordination. Video conferencing over networks is likely to be tried soon. Processor, workstation, and network use Most US ocean research centers have DECNET capability and are on SPAN. A couple of major US oceanographic institutions (University of Washington and Lamont-Doherty Geological Observatory) are not on SPAN. So far, none of the major international centers are networked with the US. Workstation capabilities are highly variable: MS/DOS and Macintosh computers with terminal emulation. SUN workstations. VAXs, wide variety of mainframes. Network use is growing rapidly. Global oceanographic experiments will put increasing pressure for installing overseas links to the networks used in the US. The international oceanographic community is well linked by TELEMAIL (OMNET). A recent printout shows 1800 users in 30 countries. This is extensively used by oceanographers for program coordination and for exchanging limited amounts of data. A majority of ocean research centers are now with SPAN. Many institutions are on TCP/IP networks such as NSFNET, USAN. There is general agreement that the system developed to meet the needs of the ocean science community should not be protocol-limited.
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Toward A National Research Network Image-transfer protocols need to be established for the community. Preferably, the protocol that is chosen will be compatible with a wider networking community. Community Issues and Concerns Privacy/proprietary rights Some sites are concerned with privacy. There is a general concern over proprietary rights, which is possibly less intense where satellite datasets are concerned. Easy Access vs. system security Community opinion on this issue is unclear; there may be a division of opinion. Most network enthusiasts seem to be for easy access. Performance & Reliability Reliability is important for interactive work: less so for data searching and dissemination. Formats and standards for ocean science data need strengthening. The GF-3 format is flexible and is widely used internationally but is not universally used. Whatever formats and standards are used by any one site, the community is looking for overall transparency in system operation. International collaboration & resource sharing Major international collaboration: Major data centers are being established (for TOGA, WOCE, GOFS, PIPOR) in the US and other countries: Canada France (TOPEX/POSEIDON) Japan West Germany United Kingdom There is need for international network connections to provide data transfers, mail, and interactive processing.
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