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Project sponsors

Project sponsors. Earth System Grid - DOE/SciDAC Coupled Energetics and Dynamics of Atmospheric Regions - NSF/GEO/ATM Virtual Solar-Terrestrial Observatory - NSF/CISE/SCI Related DODS/OPeNDAP work - NASA and NCAR/HAO. Overview. Report on experience with data ‘systems’ and data ‘frameworks’

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Project sponsors

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  1. Project sponsors • Earth System Grid - DOE/SciDAC • Coupled Energetics and Dynamics of Atmospheric Regions - NSF/GEO/ATM • Virtual Solar-Terrestrial Observatory - NSF/CISE/SCI • Related DODS/OPeNDAP work - NASA and NCAR/HAO Fox

  2. Overview • Report on experience with data ‘systems’ and data ‘frameworks’ • CEDARWEB • Earth System Grid • Compare and contrast success in terms of use(rs) • Technology integration - when and how does it work and scale? • Outline a merged approach for Virtual Observatory concept Fox

  3. CEDARWEB Fox

  4. CEDARWEB: heritage • CEDAR is a large scientific and technical community focusing on the Earth’s middle and upper atmosphere. The program features ground-based observing networks, models and integrative studies. Funded by NSF, in third phase (3rd decade) • CEDAR data history • Started as an incoherent radar database in 1983 as a tape archive (back to 1966) • Grew by late 80’s adding other instruments, models, indices • Went on-line in early 90’s (became a single-tiered data system) • Web access in 1996, three versions of the interface • Holdings - some satellite data, geophysical indices, modesl (GCM, empirical, tides, etc.), ISRs, HF Radars, Digisondes, FPIs, IR Michelson Interferometers, Spectrometers, Airglow Imagers, All-Sky Cameras, LIDARs, Multi-Channel Photometers, MST Radars, MF Radars, LF Radars, Meteor Wind Radars, Campaigns, Presentations, Surveys, Jobs, Workshops, etc. • Community, 600+, 300+ registered users, ~ 100 active data users per year • NCAR tasked with community support, and especially in the early days to ‘take care’ of the data and work with data providers and users • Significant effort in catalogs, metadata, controlled vocabulary • System has labored in getting past the code/mnemonic schemes of the past, base data format Fox

  5. CEDAR pre-web Data query, selection and retrieval interface, without any integrated tools or ability to preview data before retrieving it. Fox

  6. CEDARWEB 2.0 Fox

  7. CEDARWEB 2.0 Fox

  8. CEDARWEB 3.x Data query, selection and retrieval interface, with integrated tools, e.g. ability to plot (preview) data before retrieving it. Fox

  9. CEDARWEB - OPeNDAP Fox

  10. CEDARWEB - OPeNDAP Fox

  11. CEDARWEB 3.1 Ability to quickly plot data to assess suitability, quality, and produce a quick copy with some customization for a preliminary study. Fox

  12. Experience: CEDARWEB Don’t just provide data, but also build in community information and ancillary information that is of value. Fox

  13. Inside CEDARWEB • Rich metadata; categorized • OPeNDAP for data access and transport • MySQL for catalog and user records • https and cookies for session authentication • Script-enabled interface with plotting built in (ION) delivers html to browsers • ‘Hides’ organizational data record structure (sort of) • Low-level data product, but also high-level • Disconnect between delivery of data and attributes • Today: framework is inside the data system! Fox

  14. Experience: CEDARWEB CEDARWEB has been developed and improved over more than 10 years of interaction with users, data providers, and a community steering committee. Each of these elements has directly contributed to changes in what services are provided, what information and materials are made available via the web site and what levels of authorization and authentication are required. Biggest lesson: systems approach has worked because of the heritage of the data collection but users (esp. new or very experienced) see a barrier to entry and don’t understand where system starts/stops. http://cedarweb.hao.ucar.edu Fox

  15. Earth System Grid Overview • The goal of ESG is to make climate data – particularly climate model data – an easily accessible community resource. The project is funded by the SciDAC program: Scientific Discovery through Advanced Computing. • Enabling researchers to understand and make effective use of very large, distributed climate datasets is critical. The broad strategy is to develop a collection of server-side capabilities – minimize the amount of data movement. • Multiple interfaces to ESG will allow researchers to focus on science rather than issues of data transfer, format, and data set manipulation. • Foundation is Globus Grid technology Fox

  16. ESG: U.S. Collaborations & Development ANL: Computational grids, & grid-based applications LBNL: Climate storage facility LLNL: Model diagnostics & inter-comparison USC/ISI: Computational grids, & grid-based applications ORNL: Climate storage & computational resources LANL: Next generation coupled models & computing NCAR: Climate change predication and scenarios Fox

  17. ESG leverages existing software and projects • DODS/OPeNDAP:Distributed Oceanographic Data System (Unidata) • Integrations of Globus GridFTP, DODS data access • THREDDS: THematic Real‑time Environmental Distributed Data Services (Unidata) • LAS: Live Access Server (NOAA Pacific Marine Environmental Laboratory) • Works with CDAT, Ferret, GrADS, … • CDAT: Climate Data Analysis Tools (PCMDI), includes CDMS: Climate Data Management System, VCDAT visualization • Community Data Portal project (NCAR) • NCL (NCAR) • Globus Grid technology(ANL, ISI): GridFTP, CAS Community Access Portal Fox

  18. ESG: Requirements & Priority Matrix Fox

  19. ESG: ESG-II Architecture Fox

  20. The Earth System Grid DATA storage SECURITY services METADATA services TRANSPORT services LBNL ANALYSIS & VIZ services MONITORING services gridFTP server/client HRM FRAMEWORK services DISK ANL Auth metadata NCAR MySQL GSI CAS server RLS SLAMON daemon TOMCAT AXIS GRAM CAS client GSI NCL openDAPg client LAS server NERSC HPSS gridFTP server/client HRM openDAPg server ORNL NCAR MSS DISK TOMCAT LLNL SLAMON daemon CDAT openDAPg client MySQL Xindice RLS THREDDS catalogs gridFTP server/client HRM gridFTP server/client HRM CAS client MyProxy client MyProxy server GSI ORNL HPSS DISK DISK openDAPg server ISI MySQL MySQL RLS MySQL Xindice RLS MCS OGSA-DAIS Fox CAS client GSI GSI GSI

  21. Earth System Grid Portal Fox

  22. Community Data Portal Free text search Authentication Applications Live Access News THREDDS catalog Fox

  23. Community Data Portal Fox

  24. LAS/CDAT: Example of a Web-based Data Portal • Technology: Web Based (end user requirements) • LAS, DODS, ESG (i.e., Globus), CDAT • Portal should hide/simplify the Grid for users • Single sign-on • Community-based authorization • Simplified resource location • Remote job submission, management • Accesses the ESG Grid Testbed Fox

  25. ESG: Example of a Web-based Data Portal (serving 40+ simulations: AMIP, CMIP, and PCM) Fox

  26. ESG: Example of a Client Application Fox

  27. Metadata-centric view of ESG services DATA TRANSPORT USER AUTHENTICATION AND AUTHORIZATION LOCATION METADATA DATA ANALYSIS & VISUALIZATION ACCESS AND AUTHORIZATION METADATA AGGREGATION METADATA METADATA SERVICES CATALOGUING METADATA CONTENT METADATA DATA BROWSING ANNOTATION & HISTORY METADATA LOGGING METADATA SYSTEM MONITORING AND CONTROL DATA SEARCH & DISCOVERY Fox

  28. ESG Metadata Services Architecture 3-layer architecture: • Metadata Holdings: physical metadata content, stored in a system of relational and/or XML native databases • Core Metadata Services: modules and libraries that mediates all access to the Metadata Holdings (insert, update, delete, query) – expose an API that hides the specific implementation of the databases and query languages • High Level Metadata Services: system of applications that make use of the Core Metadata Services to fulfill a specific atomic functionality – will be invoked by external clients Fox

  29. ESG CLIENTS API & USER INTERFACES PUBLISHING ANALYSIS & VISUALIZATION SEARCH & DISCOVERY ADMINISTRATION BROWSING & DISPLAY HIGH LEVEL METADATA SERVICES METADATA EXTRACTION METADATA ANNOTATION METADATA & DATA REGISTRATION METADATA BROWSING METADATA SEARCH, QUERY & DISCOVERY METADATA AGGREGATION METADATA VALIDATION METADATA CONVERSION METADATA DISPLAY CORE METADATA SERVICES METADATA ACCESS (update, insert, delete, query) SERVICE TRANSLATION LIBRARY METADATA HOLDINGS Replica Location Services Metadata Cataloguing Services THREDDS catalogs XML DB Fox

  30. ESG Metadata Services Goal Functionality • Services responsible for the creation, management and utilization of metadata associated with geophysical data • Functionality: • Metadata extraction (automatically, from files in different format and according to various possible metadata standards) • Metadata conversion (from one standard to another) • Metadata aggregation (associated with data collections) • Metadata annotation (manually by humans) • Metadata validation (basic quality control of metadata) • Registration (population of metadata holdings) • Harvesting (combination of metadata from different repositories) • Metadata browsing and display (for humans) • Search and discovery of data through metadata • Metadata query (by agents or clients for data analysis and visualization) Fox

  31. ESG Metadata Services Current Development Currently have in production the following technologies : • Replica Location Services : database to manage and index multiple copies of the same data stored at different centers • Metadata Cataloguing Services : relational database to store scientific metadata (developed for high energy physics and geophysical data) • XML native (**) and SQL databases • THREDDS (by Unidata ) : system for hierarchical cataloguing of datasets and associated metadata (http://www.unidata.ucar.edu/projects/THREDDS) • NcML (Netcdf Markup Language) : XML language for encoding of metadata associated with data in netcdf format (and more…) Fox

  32. ESG Metadata Policy • Premise : geophysical sciences are too broad and complex to impose a single, omnicomprehensive metadata standard to capture the relevant information for all datasets, projects, instruments, scientists • ESG will not mandate use of any metadata schema or convention • Allow data providers, scientists to use their metadata of choice, provide technologies and tools to store and access metadata through common services (MCS, XML DB, THREDDS catalogs) • Encourage development and reuse of a limited set of domain-specific standards (climate data, radar data, airborn instrumentation etc), encoding in XML (according to community developed schemas), interoperability and combination of schemas (XML namespaces and RDF-based ontologies - developed but not used) Fox

  33. OPeNDAP for ESG II • DODS since ~ 1995 was been based on http and cgi-style architecture • Two concerns • Application support and performance of HTTP • Housekeeping abilities of cgi architecture • Solution evolve OPeNDAP the discipline neutral aspect of DODS Fox

  34. OPeNDAP ctd. • Data transport protocol and access protocol separated • Revised server architecture • Address Grid-style authentication • Memory management • Exception handling • All these changes and retain interoperation with HTTP and cgi • Advanced requirements: URL should support more than one dataset, or object, i.e. aggregation Fox

  35. Simple and easy to install One CGI process per URL request Limited memory management – external Limited scalability Limited status reporting to web server Returns data stream from one format Standalone server or httpd module Can manage multiple daemon processes Strong memory management – internal Reuse processes, scales Coupled to OPeNDAP server for status Returns multiple formats in a single stream, multiple protocols OPeNDAP 3.x vs OPeNDAP-g Architecture Fox

  36. Fox

  37. Application development Fox

  38. Status • Refactor core classes to remove http/libwww, etc. • Operational/production release of standalone OPeNDAP server (no dependence on web server) • Multi-protocol support: file, http, GridFTP, ftp, etc. • Re-architected for aggregation support and performance • Run OPeNDAP server as a client to GridFTP server • Portal application client in production, prototype of netCDF client operational • Authentication is handled outside OPeNDAP server • URL syntax is more complex Fox

  39. ESG: Framework experience • ESG is a highly collaborative effort and will allow users to quickly access data storage facilities storing petabytes of raw or processed data in an application independent manner. • Payoffs of this distributed collaborative infrastructure have included: • Distributed data-sharing, RLS works! SRM/HRM work! OPeNDAP-g works! • Simplified data discovery of climate data, the work on metadata paid off! Scalability? • Large-scale climate data processing and analysis via highly integrated portal • Increased collaboration among climate research scientists, people use it! • Aid in climate assessments and estimates of future climate variability and trends, IPCC! • Authentication and authorization have been a significant challenge • GSI to CAS • MyProxy - session based and seems to work well, more compatible with heterogeneous framework services • SAML is working for multi-file batch transfer Fox

  40. ESG: Framework experience • Privatization • Portal interface (and much of the holdings) are cloned • Closed communities are breeding dead-end alley developments, e.g. delivering netCDF • Transport - GridFTP versus HTTP • Server to server • Very good performance • Depends on a very specific version of GRIDftp server (stripped) • Clients are not as capable due to ‘weight’ of globus, revert to HTTP • Scalability and response times (data AND metadata) • Framework architecture supports re-layered for tuning • Service monitoring • to support the distributed collaborative infrastructure • need lots or all services to really make a production environment work • Many Globus services not used (GRIS, MDS, GIIS, … ) • Feeling lucky? Try out ESG by visiting the website at: http://www.earthsystemgrid.org Fox

  41. Success? • Users are generally happy • Exploited new technology components • Integration - when and how does it work and scale? • XML • SQL • DODS • OPeNDAP and OPeNDAP-g • Portals • P2P - clients are not as ready as we think • Globus provides a suite of framework components, some are easier to integrate than others, some just don’t fit our use-cases and architecture • Data framework - e.g. OPeNDAP has been extremely successful Fox

  42. User needs In discussions with data providers and users, the needs are clear: ``Fast access to `portable' data, in a way that works with the tools we have; information must be easy to access, retrieve and work with.'’ Too often users (and data providers) have to deal with the organizational structure of the data sets which varies significantly --- data may be stored at one site in a small number of large files while similar data may be stored at another site in a large number of relatively smaller files. There is an equally large problem with the range of metadata descriptions for the data. Users often only want subsets of the data and struggle with getting it efficiently. One user expresses it as: ``(Please) solve the interface problem.'' Fox

  43. Vision for building science cyberinfrastructure Use-case, then requirements Then derive architecture and choose technology components Build a working system for users from the start Get your funding source and community to commit to an evolving architecture If you choose a major framework technology, e.g. Globus, OPeNDAP, THREDDS, partner with them Data framework - e.g. OPeNDAP has been extremely successful Fox

  44. One paradigm Goal - find the right balance of data/model holdings, portals and client software that a researchers can use without effort or interference as if all the materials were available on his/her local computer. E.g. The Virtual Solar-Terrestrial Observatory (VSTO) is proposed to be: • a distributed, scalable education and research environment for searching, integrating, and analyzing observational, experimental and model databases in the fields of solar, solar-terrestrial and space physics Comprises: • a system-like framework which provides virtual access to specific data, model, tool and material archives containing items from a variety of space- and ground-based instruments and experiments, as well as individual and community modeling and software efforts bridging research and educational use Fox

  45. Virtual Observatory? Need better glue • Basic problem: schema are categorized rather than developed from an object model/class hierarchy -> significantly limits non-human use. However, they all form the basis to organize catalog interfaces for all types of data, images, etc. • This limits data systems utilizing frameworks and prevents frameworks from truly interoperating (SOAP, WSDL only a start) • Directories, e.g. NASA GCMD, CEDAR catalog, FITS (flat) keyword/ value pairs, are being turned into ontologies (SWEET, VSTO) • Markup languages, e.g. ESML, SPDML, ESG/ncML are excellent bases • Evolve, recast, merge (where appropriate) using formal processes, tools with intended use in mind - for interface specifications, reasoning, validation, etc. beyond the usual search and access Fox

  46. Summary • Basic success in both data systems and data framework approaches • Satisfying user and sponsor needs (from ‘just’ to ‘outstanding’) • Experience with Globus ranges from very good, to not ready for our need • Experience with OPeNDAP is very good, especially with core services • Scalability and performance require an adaptable architecture which is something system-level interfaces can still hide from the user • Challenge - to bring these attributes to a framework, i.e. in which the user is more exposed • Interoperate, interoperate, interoperate - interface, interface, interface • User interfaces still require significant HCI efforts • Metadata services are extremely important Fox

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