GIS-T Stovepipes: Barriers to Geospatial Interoperability David Loukes, P. Eng. Geoplan Consultants Inc.

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GIS-T Stovepipes: Barriers to
Geospatial Interoperability
David Loukes, P. Eng.
Geoplan Consultants Inc.
March 26, 2002
Atlanta, GA
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GIS-T Stovepipes
Presentation Overview
• Stovepipe technology issues:
Lack of GIS-T interoperability standards
Proliferation of personal geodatabases
Technology architecture complexities
IP issues
• Parting thoughts
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GIS-T Stovepipes
Geospatial Trends
• NSDI / GSDI initiatives
• Advanced, more accurate data collection
methodologies
• Move toward web enabled applications
• Concern over IP issues
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GIS-T Stovepipes
National / Global SDI Initiatives
• There is a growing interest in national and
international Spatial Data Infrastructure (SDI)
initiatives
• National:
NSDI (US)
CGDI (Canada)
Others … 27 nations in 1998 (U. of Maine)
• Growing international commitment for a
Global Spatial Data Infrastructure (GSDI)
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GIS-T Stovepipes
Today: Global Reach On the Way
Clearinghouse Sites
Gateways
Others
Web
Client
FGDC
CEONet
Source: Mark Reichardt,
US FGDC
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Others
GIS-T Stovepipes
Node
Node
Node
Node
Node
Node
Node
Node
Node
Node
Node
Node
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GIS-T Stovepipes
(G)SDI Emerging Standards
•
•
•
•
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ISO TC 211 / 204
Open GIS Consortium
ISO/JTC1 SC32 - SQL/MM
Others ...
GIS-T Stovepipes
The DOT Role in NSDI / GDSI
• NSDI / GSDI initiatives moving toward
interoperability – access to geospatial data
across organizational boundaries
• DOTs and other transportation agencies have a
considerable amount of data that should be
contributed to these initiatives
CGDI studies have clearly identified transportation
network data as the number 1 priority among users
• Result: “enterprise GIS-T” extends far beyond
the boundaries of any one transportation
agency
• Example: the GeoConnections National Road
Network initiative
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GIS-T Stovepipes
National Road Network (NRN)
• Being developed by Natural Resources Canada
as part of the GeoConnections program
• Objectives:
Develop transportation network “core” data in
support of the CGDI
Provide a framework upon which “value added”
data can be overlaid
• Concept: collect data once, as close to the
source as possible, and share across
jurisdictional boundaries
• The NRN will likely incorporate a LRS data
model in support of provincial and municipal
road network data requirements
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GIS-T Stovepipes
The GIS-T Data Model Stovepipe
• Open GIS standards for interoperability so far
are restricted to simple features (points, lines,
polygons)
• A great deal of the useful attribution related to
transportation networks is stored as LRS
events along routes
• There are no open standards at present for the
GIS-T data model extensions necessary to
support the transfer of LRS event data features
among unlike systems
• Result: the GIS-T data model stovepipe
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GIS-T Stovepipes
GIS-T Data Model Research
• Current “best practice” transportation data
model standards need to be integrated
NCHRP 20-27 (3)
ISO GDF
others?
• The “new and improved” transportation data
model needs to be incorporated into the Open
GIS standards
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GIS-T Stovepipes
Advanced Data Collection Methods
• Many advanced data collection technologies are
now available:
GPS
Digital videolog
Multi-purpose vehicles
Had-held and voice activated computers
Others …
• These technologies have made it far easier to
collect transportation infrastructure data
quickly and with improved location accuracies
• Result: proliferation of personal / workgroup
geospatial databases due to stovepipe issues
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GIS-T Stovepipes
GIS-T Data Collection Stovepipes
• The technologies are easy to use and cost
effective
• It is often possible to justify the acquisition of
these systems in support of very specific
applications
• Result:
Data may not be collected according to corporate
geospatial data standards
Differing accuracies may make integration with
existing data layers difficult
Multiple road centerline representations exist
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GIS-T Stovepipes
Data Standards Stovepipe Issues
• Project based data collection missions
may not adhere to corporate data
standards for:
Location (LRS, coordinate framework)
Attributes (fields, allowable values)
Metadata (lineage tracking)
• Result: inability to integrate data into
corporate road asset databases
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GIS-T Stovepipes
Accuracy Stovepipe Issues
• Mixed accuracies:
Existing GIS-T basemaps and road network
features commonly based on 1:10K – 1:24K
compilation specifications, with associated
accuracies of +/- 2.5 meters or greater
GPS data collection methods can now achieve submeter positional accuracies
• Result: features show up “in the wrong place:
Signs appear on the wrong side of the road
Bridges are not positioned over rivers / streams
Anchor points don’t fall on topological nodes
• Reconciliation of these problems may be time
consuming and expensive
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GIS-T Stovepipes
Centerline Stovepipe Issues
• With GPS, it is possible to collect a new road
centerline during each data collection mission.
• This presents the following issues:
Do you update the network geometry after each
mission?
How do you filter out unnecessary shape points?
How do you reconcile the new geometry to the
existing base network:
• Which nodes should be moved?
• Does the associated LRS need to be updated?
• Result: data may not be used
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GIS-T Stovepipes
Architecture Complexity Issues
• Technology architecture: we have (evolved?)
from mainframe to workstation to PC to Client
- Server to web-based
• We are now dealing with “n-Tier” architectures
and many components (“Plug and Pray”)
• What happens when something goes wrong?
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GIS-T Stovepipes
Multi-tier Architecture for Components
GIS
& applications
(ESRI, CARIS, INGR)
DB servers
Integration Tools
Tools for modeling,
cleaning, integrating
and loading data.
File servers
Access Tools
Tools for query, analysis
and reporting.
(Web-based preferred)
App Servers
Data Management Tools
Object-Relational DBMS + with Spatial
enhancements
Ref: Kucera, H., “The Open GIS Consortium … a focus on interoperability”
GIS-T Stovepipes
Tier 2
Application
Servers
File manager
Data files
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Application
Environments
Data Access
Protocols &
APIs
Network Interface APIs - (OGDI, OGC & CGI)
Meta-Data Management (Repository)
Tier 3
Tier 1
Data Management
&
Data Server
Environment
IP Issues
• In the IT community, it’s never the technology
that’s the primary barrier to data integration /
interoperability
CGDI framework and NGTN studies: the main
barriers are associated with intellectual property
(IP) issues: cost, licensing, copyright
• In Canada, cost recovery programs have
seriously impeded data sharing
Now trying to overcome these barriers
• Don’t repeat our mistakes!
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GIS-T Stovepipes
Final Thoughts …
• General GIS interoperability is achievable in
the near term
• Specific GIS-T interoperability (ie, LRS) is
farther out
• Neither is possible without some convergence
on data model and data content specifications
for the spatial database
• Field data collection needs to be carried out
within a corporate data standards context
• Geospatial data is a corporate resource
The enterprise extends far beyond DOTs
• Don’t let IP issues drag you down
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GIS-T Stovepipes
Changing Face of GIS
GIS-Centric
Applications
Spatially Aware Applications
exor app
Desktop GIS
Browser
GIS
Spatial
Processing
Digital
Maps
Text
Data
Spatially Enabled
Database
Source: Graham Stickler, Exor Corporation
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GIS-T Stovepipes
Discussion?
• This is one perspective
• There are many others …
• Let’s hear from you!
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GIS-T Stovepipes
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