1. 1 The MOCHA Project Goals: –Transparent access to distributed data sources –Scaleable middleware architecture –Automatic deployment of code (Plug-N-Play) –On-site processing and “filtering” of data –Reduction of data movement over Internet –Built upon Java and XML standards

2. 2 MOCHA 3 -Tier Architecture Clients –Web-based (applets) Query Processing Coordinator –Metadata for schema translation –Java Code Repository (types and methods) Data Access Provider –Data translation –Data filtering Data Server –Repository of metadata and data products

3. 3 Plug-N-Play Code Deployment Select location, Composite(image) From Rasters Where week BETWEEN t1 and t2 Group By location Client Oracle Informix DAP QPC Code Repository Catalog Internet Virginia Maryland Virginia Texas QQQQ Q Q QQ Q

4. 4 Plug-N-Play Code Deployment Select location, Composite(image) From Rasters Where week BETWEEN t1 and t2 Group By location Client Oracle Informix DAP QPC Code Repository Internet Virginia Maryland Virginia Texas Catalog 200MB tuples 100MB tuples results 200KB results 150KB results 150KB results 200KB results 150KB results 200KB results 350KB results 350KB

5. 5 MOCHA Features Uniform access to distributed data –Integrated schema for multiple sites Platform independent solution –Java and XML Fully extensible –User-defined types and methods (MOCHLETS) Access data in their existing formats –On-site retrieval and processing of live data

6. 6 MOCHA Features Automatic code deployment (Plug-N-Play) –Easy to administer –Easy to extend and upgrade “Light-weight” data access layer –Easy to customize, install, and enhance XML-based metadata for –System catalog –Data products Efficient Query Processing –Minimize data movement over Internet

7. 7 Advantages Over Previous Solutions Web-based Thin Clients –Single point of access to the system: QPC Easy and inexpensive to configure –Users need not be aware of low-level details (data sites, data servers, schemas, …) Unlimited Extensibility –SQL and XML query services (no inefficient scripting) –Customizable types and user-defined methods ( MOCHLETS ) Scaleable –Easy to add new services, sites, code, and clients

8. 8 Project Status Operational System –Multi-threaded QPC with catalog and code repository –Relational and XML DAPs –Data Sites 3 servers with relational DAPs 1 high-performance SP2-HPSS data repository Demonstrated at ACM SIGMOD 2000 Conf. –Access TM, AVHRR and GIS Data Products –Web demo: http://mocha.umiacs.umd.edu Future work –Deployment on ESIP Federation