1. http://www.ngs.ac.ukhttp://www.nesc.ac.uk/training OGSA-DAI Presented by Mike Mineter (Most) slides from Neil Chue-Hong (EPCC)

2. EU project: RIO31844-OMII-EUROPE 2 (at least) 2 approaches to data on Grids are needed Simple data files on grid-specific storage Middleware supporting –Replica files to be close to where you want computation For resilience –Logical filenames –Catalogue: maps logical name to physical storage device/file –Storage –Transfer Solutions include –gLite data managment –Globus: Data Replication Service –Storage Resource Broker Other data! e.g. …. –Structured data: RDBMS, XML databases,… –Files on project’s filesystems –Data that may already have other user communities not using a Grid Where do not want to replicate onto grid storage. Require extendable middleware tools to support –Computation near to data –Controlled exposure of data Based on Grid AuthN, AuhZ Basis for integration and federation “Data services” are needed OGSA –DAI –In Globus 4 –Not (yet...) in gLite, UNICORE, CROWN… On NGS

3. NGS: Application Developer Training3 Overview What is OGSA-DAI What you can do with OGSA-DAI How do you use OGSA-DAI on the NGS (hidden slides) Workflow in OGSA-DAI What’s coming up in OGSA-DAI v3.0? Where you can get more information

4. NGS: Application Developer Training4 Data Service Challenges Diversity Scale Ownership Security of data resource types, vendors, middleware, schema, metadata of collections, formats, geographical, political and social distance on individual, group, and organisation levels; intersecting yet independent for client, service and data owner; at many levels, with many tradeoffs

5. NGS: Application Developer Training5 What is a data service? An interface to a stored collection of data –e.g. Google and Amazon –web services But the data could be: –replicated –shared –federated –virtual –incomplete Don’t care about the underlying representation –do care about the information it represents Adding a service layer to existing data sources can improve composability

6. NGS: Application Developer Training6 Use Cases for Data Services Data Filtering: –Single source producing large amounts of data distributed to many sites downstream Data Discovery: –many sources, many query entry points in a linked system Data Translation: –source to sink, conversion of data model / structure Data Federation: –many sources, linked to provide view as a single source Data Replication –full or partial copies to improve throughput Data Integration (model aggregation) –e.g. integration of time variant data, streams, files Data Integration (knowledge expansion) –forming links between databases to increase knowledge

7. NGS: Application Developer Training7 Data Service Spec Goals Make access transparent Make integration easy Make management simple Impose standard interfaces to:

8. NGS: Application Developer Training8 OGSA-DAI In One Slide Extensible Portable Easy to develop We provide the generic You develop the specific Diverse, independently curated data sources

9. NGS: Application Developer Training9 OGSA-DAI In One Slide OGSA-DAI is a Java-based product that allows diverse, independently curated data resources to be exposed via Web services An extensible framework for data access and integration. Interact with data resources: – Queries and updates. – Data transformation / compression – Data delivery. Customise for your project using – Additional Activities – Client Toolkit APIs – Data Resource handlers Move computation to data A base for higher-level services – federation, mining, visualisation

10. NGS: Application Developer Training10 Overview What is OGSA-DAI What you can do with OGSA-DAI How do you use OGSA-DAI on the NGS Workflow in OGSA-DAI What’s coming up in OGSA-DAI v3.0? Where you can get more information

11. NGS: Application Developer Training11 MySQL OGSA-DAI service Engine SQLQuery JDBC Resources Handlers Activities DB2 The OGSA-DAI Framework GZipGridFTPXPath XMLDB XIndice readFile File SWISS PROT XSLT Data Resources Application Client Toolkit KEY

12. NGS: Application Developer Training12 MySQL OGSA-DAI service Engine SQLQuery JDBC SQL JDBC SQL JDBC SQL JDBC SQL JDBC Multiple SQL GDS SQLQuery SQLBag Example

13. NGS: Application Developer Training13 Making data accessible Images from UNIDART and ConvertGRID projects Bringing together PUBLIC and PRIVATE data

14. NGS: Application Developer Training14 Demographic forecasting Census DB Borders DB WFS JDBC OGSA-DAI SQL WFS GLS Join Feature Portrayal GLS Portal Map Server Receive ticket for results Retrieve annotated image Store image on server Send parameterised query FPS Call out to existing FP service Cache attributes Stream polygons Request attributes Request features Run algorithm Stream relevant annotated polygons Concentrate on algorithm Reuse generic functionality Utilise existing services Efficient delivery methods

15. NGS: Application Developer Training15 Other common patterns Robust vertical integration (eDIAMOND, GeneAssociationAnalysis) –the more results you can get, the better confidence interval you have Content-based retrieval (AHDS) –queries are based on performing some computation/querying within the initial result set, e.g. for images, videos Shared annotation systems –common data sets, personal annotations –annotations shared and queryable for greater relevance

16. NGS: Application Developer Training16 Overview What is OGSA-DAI What you can do with OGSA-DAI How do you use OGSA-DAI on the NGS Workflow in OGSA-DAI What’s coming up in OGSA-DAI v3.0? Where you can get more information

17. NGS: Application Developer Training17 Outline What is it? “Let us out” –Exposing data to clients – the server’s perspective “Let us in” –Getting to the data – the client’s perspective “More, more more…” –Extending OGSA-DAI

18. NGS: Application Developer Training18 Data resource accessors Interfaces between data resources and OGSA-DAI Relational –JDBC drivers –java.sql.* XML –XMLDB API and compliant drivers –org.xmldb.api.* File system –Java file and directory utilities –java.io.* Data Resource Accessor Relational XMLDB Data Resource Accessor Files

19. NGS: Application Developer Training19 Data service resources Data Resource Accessor Relational XMLDB Data Resource Accessor Data Service Resource Files Data Service Resource SQLOne XMLOne FilesOne

20. NGS: Application Developer Training20 Data service resources OGSA-DAI’s core functionality Manages –Access to a data resource via a data resource accessor –Execution of data-related activities –Data caching and streaming of data to and from clients –Creation, access and termination of sessions Exposes data service resource properties –Information about a data resource –Information about supported activities –Information about current requests

21. NGS: Application Developer Training21 Requests and responses Data Resource Accessor Data Service Resource SQLOne Relational SQL Query Results Perform Document Response Document ResultSet

22. NGS: Application Developer Training22 OGSA-DAI Request/Response Request OGSA-DAI Data Service Response Activity A 3 rd Party Activity BActivity C DB

23. NGS: Application Developer Training23 Requests and responses Request –A connected collection of activities that the data resource executes –Flow control – sequential or parallel execution of activities –XML perform document submitted by a client Activity –An individual data-related operation –0 or more inputs and 0 or more outputs Response –Status of execution of a request possibly with result data –XML response document returned to a client OGSA-DAI engine –Parses requests, executes activities, builds responses

24. NGS: Application Developer Training24 Example OGSA-DAI Request sqlQueryStatement SELECT * FROM Bands WHERE name = Bangles; sqlResultsToXML deliverToURL ftp://www.musicplace.org/bands/Bangles.html xslTransform deliverFromURL http://www.someplace.org/styl esheets/webRowSetToHTML.xsl ResultSet XSL HTML WebRowSet

25. NGS: Application Developer Training25 Activities Resource-specific –Relational –XMLDB –Files –Multi-resources Transformation and compression Delivery Resource creation and destruction

26. NGS: Application Developer Training26 Data services Data Resource Accessor Relational XMLDB Data Resource Accessor Data Service Resource Files Data Service Resource SQLOne XMLOne FilesOne Data Service

27. NGS: Application Developer Training27 Core features of OGSA-DAI Data access, insert and update –Relational: MySQL, Oracle, DB2, SQL Server, Postgres –XML: eXist, XIndice –Files – CSV, BinX, EMBL, OMIM, SWISSPROT,… Data delivery –SOAP over HTTP –FTP; GridFTP –E-mail –Inter-service Metadata extraction Data transformation –XSLT –ZIP; GZIP –Projections Security –X.509 certificate based security Multi OS support –Java 1.4/1.5 based Client API Documentation/ Tutorials

28. NGS: Application Developer Training28 Data Services Web services –Expose 0..N data service resources to the outside world Two flavours –OGSA-DAI WSRF services –Compliant with the Web Services Resource Framework –Implemented using Globus Toolkit (4.0+) –OGSA-DAI WSI services –Compliant with vanilla WSDL –Implemented using Apache Axis (1.2.1 or 1.2RC3)

29. NGS: Application Developer Training29 Clients and the client toolkit Clients interact with data services via SOAP over HTTP –Deduce service interface from service WSDL description –Construct SOAP request to invoke operation –Parse SOAP response from service –Resource identification scheme must be assumed from WSDL namespace OGSA-DAI client toolkit: –Construct and submit requests in Java not XML –Toolkit handles SOAP request construction and response parsing –Renders OGSA-DAI service types transparent –Java abstractions of –Data services –Data service resource IDs and session IDs –Requests and responses –Activities

30. NGS: Application Developer Training30 Authorization Data Resource Accessor Data Service Data Service Resource Client Perform Document SQLOne Relational Perform Document SQL Query ResultSet SQL Query Results Response Document Authorization points Also able to perform per activity authz

31. NGS: Application Developer Training31 Identifying a data service resource Data Service Data Service Resource Client Request SQLOne http://host:port/services/axis/DataService/DAISQLOne http://host:port/services/wsrf/DataService Request

32. NGS: Application Developer Training32 Relational multi-resources Multiple Data Resource Accessor Multi Resource Data Service Resource MultiOne Data Service Data Service Relational SQL Query Multi Results SQL Query Results x M Data Service Resource Data Service Relational SQL Query Results SQL Query Results SQL Query Results

33. NGS: Application Developer Training33 Factory resources Factory Data Resource Accessor Factory Resource FactoryOne Data Service Resource Create Resource InstanceOne Instance Data Resource Accessor Instance Resource InstanceOne

34. NGS: Application Developer Training34 Extending OGSA-DAI Application-specific data resource accessors –Expose local or remote data resources –Expose virtual resources created by aggregation or integration –Create/destroy of persistent/transient data service resources Application-specific activities –Can be resource specific e.g query or update –Or generic e.g. transformation, compression, delivery, resource management, monitoring Application-specific authorization –Resource access –Activity execution

35. NGS: Application Developer Training35 OGSA-DAI today - what’s in a name? April 28 th 2006 It’s not release 8 –The lingering spectre of OGSI It’s release 2.2 –OGSA-DAI WSRF 2.2 –Runs under Globus Toolkit 4.0.1 and 4.0.2 –Patched version bundled with Globus Toolkit 4.1.0 –OGSA-DAI WSI 2.2 –Runs under Apache Axis 1.2.1 on Tomcat –Runs under Axis 1.2RC3 on Tomcat –Runs under OMII 3.0.1 –Patched version bundled with OMII 3.0.1 http://www.ogsadai.org.uk

36. NGS: Application Developer Training36 Resources eXist data resource support Transient data service resources Relational multi-resources

37. NGS: Application Developer Training37 Activities Relational –SQL query, update, stored procedure, bulk load, extract logical and physical schema –Convert ResultSet to WebRowSet, ResultSet to CSV, ResultSet to bytes, relational database schema to XML –Project ResultSet or WebRowSet onto a column –Extract bytes from ResultSet XMLDB –Resource and collection management, XPath, XQuery, XUpdate, bulk load Files –List directory, create, read, write and update files –Index files, search indexed files

38. NGS: Application Developer Training38 Activities Transformation and Compression –GZIP compression, ZIP archive –XSLT –Project CSV data onto a column –Distribute numerical data onto spaces –Create random sample of data Delivery –From and to URLs, files, GridFTP, remote data service resources, SOAP attachments –To servlets, SMTP, resource properties Factory –Create and destroy persistent and transient data service resources Relational multi-resources –Bag and resilient queries

39. NGS: Application Developer Training39 Then there’s… eXist data resources and XQuery BLOBs –Improved support for BLOBs in SQL query and update activities –Activity to dump BLOBs into temporary files server-side Security –Resource and activity authorization –GSI Secure Conversation message-level security for inter-service communications using data transport –OGSA-DAI WSRF only Revamped logging, exceptions and internationalization Usage –Publication of an initial set of usage scenarios and best practice

40. NGS: Application Developer Training40 …and… Bundled third-party JARs Benchmarking and performance –WebRowSet – up to 35% better than in 2.0 –resultSetToCSV activity – CSV yields up to 65% improvement compared to WebRowSet –Binary data transfer –Takes 25% of the time to transfer a binary 8MB file using SOAP attachments instead of in SOAP body –Improvements due to smaller data size and smaller SOAP messages –Limited by I/O performance rather than CPU –Numerous other improvements

41. NGS: Application Developer Training41 OGSA-DAI and the NGS 1) Host data in NGS Oracle services and use OGSA-DAI to expose them via the data nodes 2) Use OGSA-DAI clients on compute nodes to gather data from remote data sources for applications running on the compute nodes 3) Use OGSA-DAI services on the compute/data nodes to store data generated by application on the compute nodes –Security and provenance –Staging and transfer –It’s important to make sure you are doing the sensible thing with your data! compute to data or data to compute?

42. NGS: Application Developer Training42 NGS AuthN EDINA Domain Example: Map Retrieval 1) Existing service 2) Simple portal 3) Secured portal 4) Integrated portal Map DB Users DB WMS EDINA Service OGSA-DAI WMS NGS Data Node Domain Census DB JDBC OGSA-DAI SQL Portal web browser Internet

43. NGS: Application Developer Training43 ConvertGrid Facilitate comparison of data for different geographies –exploit ONS All Fields Postcode Directory –maps well to many other census, health, electoral etc. geographies –convert from source geography to a chosen target geography –achieves single signon using Athens –provide simple API using OGSA- DAI http://www.sve.man.ac.uk/Rese arch/AtoZ/ConvertGrid/ Relationship between house prices (Experian dataset) and the percentage of young people in the 16 -19 age group entering University (ONS datasets) for the London area (at 1991 Census ward level)

44. NGS: Application Developer Training44 Overview What is OGSA-DAI What you can do with OGSA-DAI How do you use OGSA-DAI on the NGS Workflow in OGSA-DAI What’s coming up in OGSA-DAI v3.0? Where you can get more information

45. NGS: Application Developer Training45 OGSA-DAI Request/Response Request OGSA-DAI Data Service Response Activity A 3 rd Party Activity BActivity C DB

46. NGS: Application Developer Training46 Example OGSA-DAI Request sqlQueryStatement SELECT * FROM Bands WHERE name = Bangles; sqlResultsToXML deliverToURL ftp://www.musicplace.org/bands/Bangles.html xslTransform deliverFromURL http://www.someplace.org/styl esheets/webRowSetToHTML.xsl ResultSet XSL HTML WebRowSet

47. NGS: Application Developer Training47 Workflow Benefits Encapsulates multiple interactions with a WS in one Moves computation closer to the data Extensible activity framework Data federation/integration Data mining Readily available functionality for data-centric web/grid applications …

48. NGS: Application Developer Training48 Workflow Distinctive Features (1) Keep everything local –We have homogeneity –Avoid data movement –Call with whole result –Separate calls –E.g. we can pass object references Activities are configured at service deployment –Cannot use any “service” you want in your workflow sqlQuery transform RS sqlQuery Service transform Service SOAP/XML

49. NGS: Application Developer Training49 Workflow Distinctive Features (2) Simple, efficient workflow language –Sequence, flow –Fits our data processing needs –Other constructs can be used at the activity level (e.g. exclusive choice – a.k.a. if-split) if-split begin if-split end A B xy pipe closes pipe closes

50. NGS: Application Developer Training50 Workflow Distinctive Features (3) Streaming model –Large quantities of data –Parallel processing (pipelining) –Implicit iteration via streaming

51. NGS: Application Developer Training51 Enactment Model A.k.a. Activity Framework Core component of OGSA-DAI It is responsible for performing tasks (activities) and streaming data DB Query Delivery block Produces data in blocks Stores and provides access to data blocks Consumes data blocks Pipe

52. NGS: Application Developer Training52 Activity Processing OGSA-DAI 2.2 Processing of blocks (and therefore activities) is controlled by the pipe – from outside the activity –processBlock() is called many times until processing is complete –Usually consumes and produces a single block per call OGSA-DAI 3.0 Processing of blocks will be controlled by the activity –process() is called exactly once –Consumes and produces blocks as necessary –Each activity in a pipeline processes within each own thread –Pipes receive and may buffer blocks until they are requested

53. NGS: Application Developer Training53 Current Model Activity A processBlock() Activity B processBlock() Request Processor processBlock getBlock block processBlock block Called repeatedly Pipe

54. NGS: Application Developer Training54 New Model – release 3 – late May 2007 Activity A process() Activity B process() getBlock process putBlock block as result Processing Service initialise process Called Once Pipe

55. NGS: Application Developer Training55 Improvements to the Enactment Model Each activity is run in its own thread –Rather than one thread per chain Each activity is called to process only once –Rather than once per block Each activity sends its result to the pipe when ready –Rather than wait to be called The pipe now buffers –Rather than delegate the request for new block Performance improvements

56. NGS: Application Developer Training56 Mobile Code Allows to ‘embed’ functionality in your workflow –Allows dynamic inclusion of new code –Extends the workflow functionality without calling to a remote service –Simple but ‘prepared’ code Mobile Code Activity AActivity B

57. NGS: Application Developer Training57 Repository of Activities MySQL OGSA-DAI service Engine SQLQuery JDBC Output Stream Client Toolkit “Trusted” Repository Process Scenarios Preprocess close to source because you can’t move the data Choose an existing transform model because the transform is complex

58. NGS: Application Developer Training58 Workflow Reconstruction Be able to identify patterns –Describe workflow nodes/edges Reconstruct part of the workflow graph –Performance Some example scenarios

59. NGS: Application Developer Training59 Scenario (1) sqlQuery RS RSToWebRowSetWebRowSetProjection WRS sqlQuery RS resultsetProjection RSToWebRowSet RS WRS

60. NGS: Application Developer Training60 Scenario (2) FTPA filename file URL FTPA filename file URL Split FTPA filename file URL FTPA filename file URL

61. NGS: Application Developer Training61 OGSA-DAI workflows Data-driven workflows to solve problems –Obtain scan data for scans since date d of embryos in stage s showing expression of gene g.

62. NGS: Application Developer Training62 Overview What is OGSA-DAI What you can do with OGSA-DAI How do you use OGSA-DAI on the NGS Workflow in OGSA-DAI What’s coming up in OGSA-DAI v3.0? Where you can get more information

63. NGS: Application Developer Training63 OGSA-DAI 3.0 Top to bottom rewrite New service and resource model APIs to write new web service layers Persistence module New activity framework –new input and output types –invocation –iteration New security framework Released Q2 2007

64. NGS: Application Developer Training64 OD3: What does this mean? You can: –Chain OGSA-DAI services together to create powerful data-driven workflows. –Create workflows that integrate and transform data from multiple data resources, including accessing multiple data resources from within the scope of a single OGSA-DAI request. –"Reskin" OGSA-DAI with application-specific presentation layers to fit particular domains (e.g. DAIS, OGC, etc). –also means it’s easier to maintain different flavours: –OMII-UK, GT4, UNICORE GS, GRIA, gLite etc. –Develop application-specific activities easily and without resorting to XML manipulation.

65. NGS: Application Developer Training65 OGSA-DAI 2.2 Resource Model

66. NGS: Application Developer Training66 An expanded resource model Data Request Execution Service Data Request Execution Resource Client Data Resource Information Service Data Resource Session Management Service Session Data Data Resource Data Data Resource Data Session Request Request Management Service MySession123 MyDRER One Two Three MyRequest123456 Perform Document → Request Response Document → Request Status Untyped XML fragments → Typed Objects

67. NGS: Application Developer Training67 Multi-resource requests Data Request Execution Service Data Request Execution Resource Client Data Resource Data Data Resource Data Data Resource Data MyDRER One Two Three Request myQuery(One) myQuery(Two) myIntegrateData deliverGridFTP Client-server interaction Service-resource association Resource-resource association Resource-database association

68. NGS: Application Developer Training68 Data transport Data Request Execution Service Data Request Execution Resource Client Data Resource DataSource Service Data MyDRER MyDR DataSink Service Request (3.0) createDataSink(MySink) myQuery(MyDR) createDataSource(MySource) Perform Document (2.2) inputStream(MySink) myQuery() outputStream(MySource)

69. NGS: Application Developer Training69 Data transport Data Request Execution Service Data Request Execution Resource Client Data Resource DataSource Service Request MyDRER MyDR MyRequest DataSink Service Request (3.0) createDataSink(MySink) myQuery(MyDR) createDataSource(MySource) Perform Document (2.2) inputStream(MySink) myQuery() outputStream(MySource) Data

70. NGS: Application Developer Training70 Data transport Data Request Execution Service Data Request Execution Resource Client Data Resource DataSource Service DataSource Request MySource MyDRER MyDR MyRequest DataSink MySink DataSink Service Request (3.0) createDataSink(MySink) myQuery(MyDR) createDataSource(MySource) Perform Document (2.2) inputStream(MySink) myQuery() outputStream(MySource) Data

71. NGS: Application Developer Training71 Data transport Data Request Execution Service Data Request Execution Resource Client Data Resource DataSource Service DataSource Request MySource MyDRER MyDR MyRequest DataSink MySink DataSink Service Request (3.0) createDataSink(MySink) myQuery(MyDR) createDataSource(MySource) Perform Document (2.2) inputStream(MySink) myQuery() outputStream(MySource) Client Data

72. NGS: Application Developer Training72 Persistence OGSA-DAI State Data Request Execution Service Data Request Execution Resource Client Data Resource Information Service Data Resource Session Management Service Session Data Session Request Request Management Service OGSA-DAI Server Another OGSA-DAI Server

73. NGS: Application Developer Training73 Persistence Caching –Reduce overheads of OGSA-DAI-database communications Allows configuration and state to persist between container shutdowns/crashes Sticky resources –e.g. data sources and sinks –In-memory – only available via server that created them API –File-based implementation for backwards compatibility –Relational implementation for compatibility with common OGSA-DAI databases –Extensibility point

74. NGS: Application Developer Training74 New Activity Model Activity A process() Activity B process() getBlock process putBlock block Processing Service initialise process Called Once Pipe

75. NGS: Application Developer Training75 Activity Interface All activities must implement the Activity interface Activities may extend the abstract BaseActivity class which implements common functionality => only need to implement process()

76. NGS: Application Developer Training76 Activity Extension Interfaces New interfaces extend the base activity to provide access to necessary information –Activities that access data resources –Activites that create new requests –Activities that are configurable –…

77. NGS: Application Developer Training77 Monitoring Monitoring Framework: Provides Listener interfaces Activity Listeners: Receive activity events, for example –Activity initialised –Activity processing –Error occurred –Processing completed –Custom events …

78. NGS: Application Developer Training78 More Listeners Pipe Listeners: Receive pipe events, for example –Block produced –Block consumed Various listeners may be implemented to support logging, auditing, debugging etc.

79. NGS: Application Developer Training79 Scalability and robustness OGSA-DAI State Client OGSA-DAI cluster Front-end Router

80. NGS: Application Developer Training80 Scalability and robustness Release 3 will afford future provision of clustering and load balancing Clustered OGSA-DAI servers –Different JVM –Different machine Load balancer –Simple e.g. round robin –Complex e.g. decide on basis of current load of each server Scalable –Increases number of requests that OGSA-DAI can handle concurrently Robust –Seamless operation in the face of errors e.g. server failures Sticky sessions and resources –Session and resource state may be non-serializable or be lightweight in-memory components –Need to dispatch resources to their “owner” JVM

81. NGS: Application Developer Training81 New security framework Information collected at various points in the system Policy Decision Points similar to previous OGSA-DAI version Allows extensibility e.g. VOMS Tries to authorize at highest sensible level –but if required will call back to higher layers from sub request object level I am not a security expert Developed in conjunction with SIMDAT and inteligrid projects

82. NGS: Application Developer Training82 Other planned features Support for registries –Guidelines on how to best use standard registries (e.g. GRIMOIRES or GT4 ServiceGroups) and tools to help you do so within OGSA-DAI Improved support for message-level and transport-level security including delegation Concurrent or closely-following releases of –A new implementation of DAIS –OGSA-DAIR and OGSA-DAIX –A refactored OGSA-DQP with a Java-compliant query compiler and which runs under Linux, Solaris or Windows

83. NGS: Application Developer Training83 Distributed Query Processing Higher level services building on OGSA-DAI Queries mapped to algebraic expressions for evaluation Parallelism represented by partitioning queries –Use exchange operators table_scan (protein) table_scan termID=S92 (proteinTerm) reduce hash_join (proteinId) op_call (Blast) reduce exchange 3,4 12

84. NGS: Application Developer Training84 DQP architecture

85. NGS: Application Developer Training85 Summary OGSA-DAI is middleware which allows uniform access to data sources which are: –diverse –heterogeneous –independently curated It is designed to be: –efficient –extensible –portable –easy to develop It brings together remote data sources at run-time. –and reduces round trips through use of workflows

86. NGS: Application Developer Training86 Further information Projects using OGSA-DAI: –http://www.ogsadai.org.uk/about/projects.php And what they’ve been doing: –http://www.ogsadai.org.uk/about/success_stories/ Learn to program OGSA-DAI: –http://www.ogsadai.org.uk/documentation/ogsadai-wsrf- 2.2/doc/clients/clienttoolkit/index.html See what’s coming up in OGSA_DAI 3.0: –http://www.ogsadai.org.uk/documentation/Design_documents/http://www.ogsadai.org.uk/documentation/Design_documents/ The OGSA-DAI Project Site: –http://www.ogsadai.org.uk The DAIS-WG site: –http://forge.gridforum.org/projects/dais-wg/

87. NGS: Application Developer Training87 Further information The OGSA-DAI Project Site: –http://www.ogsadai.org.uk The DAIS-WG site: –http://forge.gridforum.org/projects/dais-wg/ OGSA-DAI Users Mailing list –users@ogsadai.org.uk Formal support for OGSA-DAI releases –http://bugs.ogsadai.org.uk OGSA-DAI training courses (live and online)

88. Neil Chue Hong EPCC N.ChueHong@epcc.ed.ac.uk +44 131 650 5957 Questions?