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Web Services: Web Services: a Mechanism for a Mechanism for
Across-the-Internet On Demand Across-the-Internet On Demand Computing and CommunicationComputing and Communication
DMS WorkshopDMS Workshop
Stevenson, WAStevenson, WAWed 08 June 2005Wed 08 June 2005
What are Web Services, What are Web Services, and how can they be useful to us?and how can they be useful to us?
How do they work? How do they work? What's needed to make one?What's needed to make one?
Web Services - 8 June 2005
Web Services WorkshopWeb Services Workshop
David Okaya (USC) Introduction: distributed vs. local computing.David Okaya Background basics of Across-the-Internet On-
Demand service.Phil Maechling (SCEC) Four current methods of distributed computing.John Graham (Telascience) What is a Web Service? An earth scientist's
view.Dennis Sosnoski (SSS) What is a Web Service? an IT view.
John Graham (Telascience) GeoFusion and Whirlwind web services.Dogan Seber, Choohan Youn (SDSC) GEON and seismology w.s.Andrea Donnellan (JPL) QuakeSim and SERVO w.s.Phil Maechling (SCEC) SCEC Community Modeling Environment w.s.Joanna Muench (IRIS) IRIS SOSA and DHI seismogram tools.
David Okaya (USC) Summary: distributed work environments.
Motivation for Web Services workshop:Motivation for Web Services workshop:Distributed versus local computingDistributed versus local computing
DMS WorkshopDMS Workshop
Stevenson, WAStevenson, WAWed 08 June 2005Wed 08 June 2005
David OkayaDavid OkayaUniv. Southern CaliforniaUniv. Southern California
Web Services - 8 June 2005
Internet MilestonesInternet Milestones: Not that long ago!: Not that long ago!
earth scienceearth science widespreadwidespreadfeaturefeature originationorigination radar screenradar screen usageusage
Static WebStatic WebWWW - htmlWWW - html 1993 first browser1993 first browser ~1996~1996 ~2000~2000
Dynamic WebDynamic Web
search enginessearch engines 19951995 1998 Google1998 Google ~2000~2000
scripts CGI/perlscripts CGI/perl 19951995 late 1990slate 1990s ~2000 ~2000
JavaJava 1995 SUN release1995 SUN release 1998-20001998-2000 ----------
appletsapplets 19951995 late 1990slate 1990s ----- -----
servletsservlets 19971997 early 2000searly 2000s ----- -----
XMLXML 19981998 early 2000searly 2000s ----------
web servicesweb services 20012001 2002+2002+ ----- -----
Semantic Web (find, share, combine Web info via machine-readable ways)Semantic Web (find, share, combine Web info via machine-readable ways)
Web Services - 8 June 2005
Meaning of "Web Service"Meaning of "Web Service"ConceptualConceptual::
Performance of "across-the-Internet on-demand" functionality.Performance of "across-the-Internet on-demand" functionality.The requesting and computing computers are not tightly coupled.The requesting and computing computers are not tightly coupled.
Technical:Technical:
A framework for offering a functionality using specific protocols.A framework for offering a functionality using specific protocols.
"Across-the-Internet on-Demand" Distributed Computing"Across-the-Internet on-Demand" Distributed Computing
Coupled (and HTML based):Coupled (and HTML based): Loosely coupled (obj.-orient. based):Loosely coupled (obj.-orient. based):- cgi/perl- cgi/perl - java servlets- java servlets- php- php - CORBA- CORBA- javascript- javascript - java RMI- java RMI
- web services- web services
ANDAND in either case, in either case, notnot necessarily tied to an HTML web page. necessarily tied to an HTML web page.
Web Services - 8 June 2005
Benefits of Distributed Computing via Benefits of Distributed Computing via Web ServicesWeb Services
ResourcesResources•• Compute resources not locally available to requester ("client"): Compute resources not locally available to requester ("client"): computer time, storage/memory, applications.computer time, storage/memory, applications.•• Access to evolving databases and data archives maintained Access to evolving databases and data archives maintained
elsewhere.elsewhere.
FunctionalityFunctionality•• Access to a range of functionalities (very simple to high end).Access to a range of functionalities (very simple to high end).•• Original codes maintained and improved by authors, not users.Original codes maintained and improved by authors, not users.
Community EnvironmentCommunity Environment•• Sharing of codes, utilities; development of community toolkit.Sharing of codes, utilities; development of community toolkit.•• Commonality or standardization for a group of users.Commonality or standardization for a group of users.
Web Services - 8 June 2005
Examples of Web Service FunctionalityExamples of Web Service Functionality
UtilitiesUtilities•• latitude/longitude to UTM and other map projections.latitude/longitude to UTM and other map projections.•• calendar to Julian dates to epoch seconds.calendar to Julian dates to epoch seconds.•• Header dumps of formats such as DEM, miniSEED, SAC.Header dumps of formats such as DEM, miniSEED, SAC.
Formats and TranslatorsFormats and Translators•• Ascii to binary; endian swap; postscript to JPEG, JPEGs to MPEG.Ascii to binary; endian swap; postscript to JPEG, JPEGs to MPEG.•• Translation between formats such as miniSEED, SAC, SEGY.Translation between formats such as miniSEED, SAC, SEGY.
DeliveryDelivery•• Extraction from data archives; "slice & dice" of data products.Extraction from data archives; "slice & dice" of data products.•• Visualization of data products.Visualization of data products.
Research CodesResearch Codes•• Interface to scientific codes.Interface to scientific codes.•• Wrapping of scientific (legacy) codes. SAC, modeling codes, GMT.Wrapping of scientific (legacy) codes. SAC, modeling codes, GMT.
Access via web page, GUI, from within (object-oriented) codes, and Access via web page, GUI, from within (object-oriented) codes, and even command line utility.even command line utility.
Web Services - 8 June 2005
Web Services WorkshopWeb Services Workshop
David Okaya (USC) Introduction: distributed vs. local computing.David Okaya Background basics of Across-the-Internet On-
Demand service.Phil Maechling (SCEC) Four current methods of distributed computing.John Graham (Telascience) What is a Web Service? An earth scientist's
view.Dennis Sosnoski (SSS) What is a Web Service? an IT view.
John Graham (Telascience) GeoFusion and Whirlwind web services.Dogan Seber, Choohan Youn (SDSC) GEON and seismology w.s.Andrea Donnellan (JPL) QuakeSim and SERVO w.s.Phil Maechling (SCEC) SCEC Community Modeling Environment w.s.Joanna Muench (IRIS) IRIS SOSA and DHI seismogram tools.David Okaya (USC) Summary: distributed work environments.
A.M.
P.M.
EarthScope CSIT Workshop, March 25-27, 2002
SDSC/Cal-(IT)2 Information Integration Testbed
SociologyWorkbench
SOAP
WSDL
SOAP
WSDL
SOAP
WSDL
I2T Mediator
Clients
XML (GML)
XML queries
Surveydata
SOAP
WSDL
ArcIMSArcSDE
ICPSRUniv. of
Michigan
Spatial mediator DatabaseIntegration
StatsPackage
TechnologyTechnologyto automateto automatecreation ofcreation of
Web servicesWeb services(“Query Set (“Query Set
Specification”)Specification”)
Industry partners:Enosys
ESRIIBM DiscoveryLinks
Blue Titan
Spatial Spatial mediation:mediation:• Dealing with Dealing with differences in differences in resolution, scaleresolution, scale• Plug-in Plug-in conflation conflation routinesroutines• Web workflows Web workflows and Service and Service “orchestration”“orchestration”
from Chaitan Baru (SDSC)