Download GEON: Standards-based secure invocation of ArcWeb

GEON papers to be featured in moderated session (August 10, 2004,
8:30 a.m.) at 24th Annual ESRI International User Conference
ESRI UC Paper number 1692
Title
GEON: Standards-based Secure Invocation of ArcWeb Services
Authors
Memon, Ashraf, Chaitanya Baru, Ilya Zaslavsky, Steve Mock, Amit
Behere (San Diego Supercomputer Center, University of California, San
Diego)
Within the Geosciences Network (GEON) project, we implemented a secure
mechanism of data interchange across distributed spatial databases and
services, a common requirement in many geographic applications. The
paper explores OGSI-based grid services that implement Grid Security
Invocations (GSI), and describes an application of this model to secure
invocation of ArcWeb services.
Currently, ArcWeb services use single sign-on security model, in which,
on initial authentication, the user is assigned a time-limited numeric
token that is passed along with the request message and used to unlock
an ArcWeb service. We implemented a GSI authentication wrapper on top
of ESRI's token-based authentication mechanism. To invoke an ArcWeb
service on the secure grid, the user first requests a time-limited
proxy certificate by providing a user name and passphrase to a
certificate authority. This certificate, which is transmitted inside
SOAP headers of all service requests, is verified each time before a
service is invoked.
ESRI UC Paper number 1796
Title
GEON: Ontology-Enabled Map Integration
Authors
Lin, Kai, Bertram Ludaescher (San Diego Supercomputer Center,
University of California, San Diego)
In the GEON project we are developing an interoperability system on top
of ArcIMS for registering spatial data sets to ontologies and
subsequently querying registered data sets through the ontologies for
map rendering. The system consists an ontology repository, a data set
registration procedure, and a query rewriting system. User-defined
ontologies are imported as OWL files and saved in the ontology
repository. Structural and semantic heterogeneities of data sources are
resolved using information from the data set registration procedure and
ontology information. Those are used when rewriting user queries (e.g.,
a geologic age or rock type will expand to their corresponding "subconcepts" in the rewritten query). Multiple ontologies are supported
in the system by allowing users to define a morphism between two
ontologies which equates some concepts in the source ontology to some
concepts in the target ontology. Users are able to switch between
ontologies for which an ontology morphism exists.
ESRI UC Paper number 1791
Title
GEON: Assembling Maps on Demand from Heterogeneous Grid Sources
Authors
Zaslavsky, Ilya, Ashraf Memon (San Diego Supercomputer Center,
University of California, San Diego)
Integrating spatial information from multiple grid-enabled sources of
geologic data is an important component of the NSF-funded Geosciences
Network (GEON) project. The spatial integration is orchestrated by GeoGEMS (Grid-Enabled Mediation Services), a collection of grid services
that support spatial data mediation, ontology and schema conflict
resolution, and composite map assembly. Geologic data are served by
distributed ArcIMS and WMS servers, each wrapped in WSDL/SOAP wrappers.
Capabilities of each source are registered at the mediator, so that the
latter can plan and orchestrate query execution.
To produce a composite result, query results retrieved from individual
sources are either merged at the mediator or overlapped at the client.
A comprehensive GEON map assembly service represents a temporary
mediator-level ArcIMS service that is created on demand to merge
individual raster and vector fragments from distributed servers into a
composite map, and generate answers to follow-up requests without requerying the sources.
ESRI UC Paper number 1790
Title
GEON: The GEON Grid Software Architecture
Author
Baru, Chaitan (San Diego Supercomputer Center, University of
California, San Diego)
The Geosciences Network (GEON) is a multi-university project funded by
the National Science Foundation to develop cyberinfrastructure to
enable sharing of data sets and services in a distributed environment,
for the Earth Sciences. The GEON Grid is a distributed network of _GEON
nodes_, each of which runs a GEON _software stack_ that includes Web
and Grid services to enable users to register data sets; register
services; issue queries across multiple information sources, using
spatiotemporal search conditions and ontologies; download data into
personal spaces; invoke analysis services; and visualize output of
queries and/or analysis. The architecture includes data mediation
services, workflow services, and a portal. Much of the data is
geospatial and spatiotemporal in nature and providing appropriate
search interfaces and efficient mapping interfaces for such data is an
important requirement. The GEON Grid software stack will include ArcIMS
as one of its components to provide GIS and mapping functionality.
Title
GEON: ArcIMS Online Mapping to Facilitate Integration of Geoscience
Data
Author
Arrowsmith1, J.R., G. Randy Keller2, Jeff Conner1, J. Yoburn1, L.
Prashad1, C. Eisinger1, W.L. Stefanov1, M.J. Fouch1 (1=Department of
Geological Sciences, Arizona State University, Tempe, AZ 85287,
[email protected];
2=Department of Geological Sciences, University of Texas El Paso, El
Paso, TX)
The Colorado Plateau-Basin and Range Transition Zone of Arizona and New
Mexico comprises an important geologic setting in which the study of
continental crustal evolution and deformation is particularly intensive.
In addition, it is a region of rapid population growth where balancing
resource use, resource preservation, and sustainable land use is
increasingly important. To inform such efforts, we have gathered
geological data (e.g., geologic outcrops at various scales, active
fault maps), digital topography (USGS NED and SRTM 30 m), ASTER
satellite imagery, and geophysical data (e.g., gravity, heat flow,
seismicity, seismic anisotropy, magnetics, receiver functions, seismic
tomography), and integrated them using ArcIMS. We have also developed
a Java Servlet-driven IDL-cored image processing system to produce
user-specified (from imagery footprints in ArcIMS) ASTER band
combinations in GeoTiff format. This data system is an initial step in
the development of a seamless data and scientific analysis portal as
part of the GEON project.