1. 1 Gateways

2. 2 The Role of Gateways  Generally associated with primary sites in ESG-CET  Provides a community-facing web presence  Can be branded as needed by organizations or projects  Aggregates affiliated data providers (e.g. Data Nodes)  Manages local and enterprise metadata  Provides enterprise management and monitoring  Provides Virtual Organization (VO) management  Federates with other Gateways Identity, security, SSO, metadata  Large, complex software infrastructure – only a few, at least initially

3. 3 ESG-CET Gateways

4. 4 Gateway Homepage

5. 5 Functionality of Gateways  User registration  Login/authentication  Authorization  Data browsing  Data search  Data download interface and monitoring  Data products interface  Data annotation and tagging  Metadata browsing  User management  VO management  Metadata harvesting  Metrics and network logging and reporting  Model trackback interface*  Model intercomparison* * Emerging work

6. 6 Gateway Interactions

7. 7 Metadata Management is Central to the ESG  Domain object model Support all metadata needed by CMIP5 profile and other key collaborators Expand model metadata as developed by ESC (grids, boundary/forcing for simulations, etc.)  Gateways store comprehensive metadata for data published through them  Search & discovery (s&d) metadata subset is harvested into an RDF triple store  OAI-PMH provider/harvester services are used to synchronize contents of RDF triple store across all gateways Open Archives Initiative Protocol for Metadata Harvesting  All federated gateways hold s&d metadata for all ESG holdings Users can find any data from any gateway

8. 8 Gateway Technology Base  Spring Framework for Java including: Hibernate support Spring Security (formerly Acegi) Web Flow for complex workflows  Tomcat as web application container  Postgres as relational database  Hibernate for object-to-relational mapping  OWL/RDF for semantic models  Sesame Triple Store for persisting Search & Discovery metadata  OAI-PMH for metadata exchange among Gateways and partner data centers

9. 9 Gateway Technology Base  OpenID for single-sign-on across Gateways  Globus MyProxy w/ X509 certificates for rich client access  JSP/JSTL/YUI for user interface including Ajax support  Junit/Dbunit for unit, database and integration testing