Download presentation
Presentation is loading. Please wait.
1
The Problem: Integrating Data, Applications, and Client Devices The key issue we try to solve is building the distributed computing infrastructure that can connect The key issue we try to solve is building the distributed computing infrastructure that can connect Legacy data archivesLegacy data archives Executable codesExecutable codes Real time data sourcesReal time data sources Client tools for collaborationClient tools for collaboration Audio/Video systems, whiteboard annotators, etc Audio/Video systems, whiteboard annotators, etc Various application-specific grids can be built out of the common infrastructure Various application-specific grids can be built out of the common infrastructure Science GridsScience Grids Emergency planning, crisis responseEmergency planning, crisis response We choose certain fixed points for our foundations We choose certain fixed points for our foundations Other standards where available: GIS standardsOther standards where available: GIS standards Web Service standards: SOAP and WSDLWeb Service standards: SOAP and WSDL Universal messaging substrate for SOAP and other messages: http://www.naradabrokeringUniversal messaging substrate for SOAP and other messages: http://www.naradabrokering
2
OGC Standards for GIS OpenGIS Consortium is an international group that defines common formats for geospatial data and service standards. OpenGIS Consortium is an international group that defines common formats for geospatial data and service standards. Main data format language is the XML-based Geography Markup Language (GML). Main data format language is the XML-based Geography Markup Language (GML). GML is widely accepted as the universal encoding for geo-referenced data.GML is widely accepted as the universal encoding for geo-referenced data. OGC defines services. OGC defines services. Some example OGC services includeSome example OGC services include Web Feature Service (WFS): for retrieving GML encoded features, like faults, roads, county boundaries, GPS station locations,…. Web Feature Service (WFS): for retrieving GML encoded features, like faults, roads, county boundaries, GPS station locations,…. Web Map Service (WMS): for creating maps out of Web Features Web Map Service (WMS): for creating maps out of Web Features http://www.opengeospatial.org http://www.opengeospatial.org
3
What Are Web Services? Web Services framework is a way for doing distributed computing with XML. WSDL: Defines interfaces to functions of remote components. This is the programming interface. SOAP: Defines the message format that you exchange between components. This carries the messages over the network. Web Services are not web pages, CGI, servlets, applets. XML provides cross-language support Suitable for both human and application clients. We are building data grid components in the same fashion. Allows us to build general purpose client environments like Web portals and command line tools. http://www.w3.org/2002/ws Web Server DB JDBC Browser Web Server SOAP Appl SOAP WSDL
4
Service Oriented Architecture Key SOA Features Key SOA Features (Following W3C’s WS Architecture working group.) (Following W3C’s WS Architecture working group.) SOAs are composed of services that present programmatic access to resources to remote client applications.SOAs are composed of services that present programmatic access to resources to remote client applications. Services communicate using messages. Messages are usually encoded using SOAP.Services communicate using messages. Messages are usually encoded using SOAP. SOAs are metadata rich. We must describe service interfaces, provide descriptions of services and publish them into registries.SOAs are metadata rich. We must describe service interfaces, provide descriptions of services and publish them into registries.
5
Publish/Find/Bind paradigm in a GIS Grid Service providers Service requestors Service registries Service Oriented Architecture
6
NaradaBrokering (NB) NaradaBrokering is a distributed messaging infrastructure. NaradaBrokering is a distributed messaging infrastructure. It may be thought of a as topic-based publish/subscribe messaging system: It may be thought of a as topic-based publish/subscribe messaging system: interested entities can register to a NaradaBrokering node to send and receive messages on particular topics.interested entities can register to a NaradaBrokering node to send and receive messages on particular topics. It supports multiple underlying transport protocols, intelligent message routing, asynchronous messaging, reliable delivery, replay of events, compression/fragmentation, discovery etc. It supports multiple underlying transport protocols, intelligent message routing, asynchronous messaging, reliable delivery, replay of events, compression/fragmentation, discovery etc. http://www.naradabrokering.org http://www.naradabrokering.org
7
Pattern Informatics in a Grid Environment PI in a Grid environment: Hotspot forecasts are made using publicly available seismic records. Southern California Earthquake Data Center Advanced National Seismic System (ANSS) catalogs Code location is unimportant, can be a service through remote execution Results need to be stored, shared, modified Grid/Web Services can provide these capabilities Problems: How do we provide programming interfaces (not just user interfaces) to the above catalogs? How do we connect remote data sources directly to the PI code. How do we automate this for the entire planet? Solutions: Use GIS services to provide the input data, plot the output data Use HPSearch tool to tie together and manage the distributed data sources and code.
8
<soap:Header encodingStyle=“WSCTX URL" <soap:Header encodingStyle=“WSCTX URL"mustUnderstand="true"> http.. http.. <activity-list <activity-list mustUnderstand="true" mustPropagate="true"> mustUnderstand="true" mustPropagate="true"> http://../WMS http://../WMS http://../HPSearch http://../HPSearch... SOAP header for Context The Pattern Informatics GIS-SOA based workflow application 5,6: WMS starts a session, invokes HPSearch to run workflow script for PI Code with a session id 7,8,9: HPSearch runs the workflow script and generates output file in GML format (& PDF Format) as result 10: HPSearch writes the URI of the of the output file into Context 11: WMS polls the information from Context Service 12: WMS retrieves the generated output file by workflow script and generates a map http://.../HPSearch http://.../HPSearch HPSearch associated additional data generated during execution of workflow. HPSearch associated additional data generated during execution of workflow. </context> service associated http://.../WMS http://.../WMS <service>http://.../WMS</service><service>http://.../HPSearch</service></activity-list></context> session http://.../HPSearch http://.../HPSearch http://../abcdef:012345 http://../abcdef:012345 profile information related WMS profile information related WMS </context> user profile http://../abcdef:012345 http://../abcdef:012345 http://.../HPSearch http://.../HPSearch http://danube.ucs.indiana.edu:8080\x.xml http://danube.ucs.indiana.edu:8080\x.xml </context> shared state http://.../HPSearch http://.../HPSearch <parent-context>http://../abcdef:012345<parent-context/> shared data for HPSearch activity shared data for HPSearch activity <service>http://.../DataFilter1</service><service>http://.../PICode</service><service>http://.../DataFilter2</service></activity-list></context> activity 3 WMS WFS http://..../..../..txt HP Search Data Filter PI Code Data Filter http://..../..../tmp.xml Context Information Service 4 7,8,9 10 6 5,11 WMS Client Extended UDDI 0 1 2
9
The Interdependent Energy Infrastructure Simulation System (IEISS) in a Grid Environment IEISS in a Grid environment: IEISS provides modeling, simulation and analysis of interdependent energy infrastructures. Input is data models in XML format. Los Alamos National Laboratory Argon National Laboratory Code location is unimportant, can be a service through remote execution Results need to be stored, shared, annotated Grid/Web Services can provide these capabilities Problems: How do we provide programming interfaces (not just user interfaces) to the input data models? How do we connect remote data sources directly to the IEISS code? Solutions: Use a SOA with GIS services to provide the input data, plot the output data Use WS-I compatible XML metadata services to support GIS workflow applications by providing/maintaining static and dynamic information
10
WFS and WMS publish their WSDL URL to the UDDI Registry1-2-3 - WMS Client -> WMS Server -> UDDI -> WFS 4-5 - WFS publishes the results as GML FeatureCollection document into a topic (“/NISAC/WFS”) in a pub/sub based messaging system. WFS -> WMS Server (creates a map overlay) and IEISS receive this GML document. WMS Server -> WMS Client (displays it) 6 - User invokes IEISS through WMS Client interface for the obtained geospatial features, and WMS Client starts a workflow session in the Context Service.
11
7 - On receiving invocation message, IEISS updates the shared state data to be “IEISS_IS_IN_PROGRES”. IEISS runs and produces an ESRI Shape file and then invokes shp2gml tool to convert produced Shape file to GML format. After the conversion IEISS updates shared session state to be “IEISS_COMPLETED”. As the state changes, the Context Service notifies all interested workflow entities such as WMS Client.
12
8 – On receiving the notification, WMS Client makes a request to the WFS-L for the IEISS output 9-10 - WFS-L publishes the IEISS output as a GML FeatureCollection document to NB topic ‘NISAC/WFS-L’. WMS Server is subscribed to this topic and receives the GML file then converts it to map overlay, and the Client displays the new model on the map.
13
Some Challenges Security: These applications have interesting security requirements Security: These applications have interesting security requirements Authentication, authorization and priority for different usersAuthentication, authorization and priority for different users Time/event dependent security for crisis responseTime/event dependent security for crisis response Performance: Are GIS services suitable for non-trivial data transfers? Performance: Are GIS services suitable for non-trivial data transfers? We are using streaming data transfers for higher performanceWe are using streaming data transfers for higher performance We research fast data transfer methodologies for higher performanceWe research fast data transfer methodologies for higher performance Fault tolerance and scalability: We must support SOA based distributed application with reliable information sources. Fault tolerance and scalability: We must support SOA based distributed application with reliable information sources. We design and build fault tolerant and high performance decentralized Information Services to support metadata requirements of SOA.We design and build fault tolerant and high performance decentralized Information Services to support metadata requirements of SOA. Adoption: We must get the tools and services to the point where science application developers want to use them early in the development process rather than later. Adoption: We must get the tools and services to the point where science application developers want to use them early in the development process rather than later. Web Service client libraries to remote GIS dataWeb Service client libraries to remote GIS data Develop codes to work with data streams rather than files.Develop codes to work with data streams rather than files. Extensibility: This architecture can be enhanced by integrating various types of distributed data sources that can provide geospatial data such as MySQL, Oracle Spatial, ESRI SDE, Shape files etc. Extensibility: This architecture can be enhanced by integrating various types of distributed data sources that can provide geospatial data such as MySQL, Oracle Spatial, ESRI SDE, Shape files etc.
14
Location of information and software for dependent Grid Projects htpp://www.naradabrokering.org provides Web service (and JMS) compliant distributed publish-subscribe messaging (software overlay network) htpp://www.naradabrokering.org provides Web service (and JMS) compliant distributed publish-subscribe messaging (software overlay network) htpp://www.naradabrokering.org http://www.crisisgrid.org is an OGC (open geospatial consortium) Geographical Information System (GIS) compliant GIS and Sensor Grid. http://www.crisisgrid.org is an OGC (open geospatial consortium) Geographical Information System (GIS) compliant GIS and Sensor Grid. http://www.crisisgrid.org http://www.opengrids.org has WS-Context, Extended UDDI etc. http://www.opengrids.org has WS-Context, Extended UDDI etc. http://www.opengrids.org
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.