OGC’s OWS-3 Initiative: An Interview with OGC’s George Percivall
Magazine's Nora Parker asked George
Percivall, the Open Geospatial Consortium's (OGC) Executive
Director for Interoperability Architecture, to describe the OGC's
latest Interoperability Initiative, OGC Web Services 3 (OWS-3).
Percivall supervises OGC's Interoperability Initiatives, which are the
main activity within OGC's Interoperability Program.The OWS-3 kickoff
took place April 19-21, 2005 and the final demonstration of
capabilities will take place October 17-20, 2005.
Nora Parker (NP): In layman's terms, what is the OGC Web Services (OWS-3)
interoperability initiative? Why is it important and why should users
in the geospatial industry be interested in it?
George Percivall (GP): OWS-3 is OGC's next major advance in the
development of open specifications that enable geospatial
interoperability.OWS-3 involves a wide scope of activities, ranging
from the acquisition of geospatial data from sensors to defining a
"common infrastructure" for decision support.
The Sensor Web Enablement (SWE) portion of OWS-3 focuses on making
sensors accessible as enterprise Web services.The OWS-3/SWE team has
been working with a variety of sensors ranging from those in a fixed
location to ones located on cars, airplanes and satellites.The ground
based sensors network has been designed to scale to a nationwide
network.Part of this scalability is achieved by working with an IEEE
(Institute of Electrical and Electronics Engineers) standard developed
by the sensor hardware industry.The SWE work includes methods to
request an observation to be made by a sensor on a moving or moveable
The common infrastructure portion of OWS-3 involves refining the common
elements of all OGC Web Services.By using a common approach for all
service types, the software development for a new service is lessened.
OWS-3 has continued the work from a prior testbed on workflow
automation.As the variety of geospatial services continues to
increase, techniques to define and automate workflows provide users
with the long promised flexibility of Web services.To support all of
the data sharing that is needed in this distributed environment, OWS-3
has contributed new work on Digital Rights Management for geospatial
The decision support services portion of OWS-3 focuses on the end user
or analyst who needs to pull together a variety of information to
support decision making for specific circumstances.OWS-3 is defining
methods to transparently convert geospatial data from other communities
into terms familiar to the user.Key visualization services to support
decision making include flexible methods for selecting the symbols to
be displayed on a map created from various sources.
Finally, OWS-3 is beginning to define a standard for geospatially
enabled video.The Web can serve video; OWS-3 has produced a "GeoVideo
Service" specification for a standard way to tell you which part of the
world you are viewing.
NP: What impact will OWS-3 have on the industry? What end
results are expected, and what's the timing for adoption of new
GP: Like other OGC Interoperability Program Initiatives, OWS-3
has created new and revised draft specifications, implementations of
those specifications and an evocative demonstration of the resulting
capabilities.After the demo, the draft specifications will be
presented to the OGC Specification Program, that is, the Technical
Committee and the Planning Committee, for consideration to become
consensus standards.This formal process by which testbeds feed into
specification activity has been run very successfully by the OGC in
Some of the specifications will be updates to existing, mature, already
adopted specifications, e.g., the OpenGIS Web Map Service (WMS)
Specification, OpenGIS Web Feature Service (WFS) Specification, OpenGIS
Web Coverage Service (WCS) Specification and OpenGIS Geography Markup
Language (GML) Encoding Specification.Some of the specification work
in OWS-3 will enable the Specification Program to adopt specifications
that have been under consideration but that needed more work: SensorML,
Sensor Observation Service, Feature Portrayal Service and several
The timing for adoption depends on a lot of factors and it's hard to
predict, because all the members can suggest changes at any time.We
will know more after the next Technical and Planning Committee meetings
in Bonn, Germany, the second week in November.
New draft specifications developed in OWS-3 will begin working their
way through the consensus process as discussion papers.The GeoVideo
Service, for example, is a new discussion paper that is coming out of
NP: Who are the sponsors and what are they expecting to gain?
What is the budget, and does it come solely from the sponsors?
sponsors include: BAE Systems, IONIC Software, GeoConnections (Canada),
Lockheed Martin, MAGIC Services Initiative, National Aeronautic and
Space Administration (NASA), Oak Ridge National Laboratory (ORNL),
NAVTEQ, Questerra, US Geological Survey (USGS) and other organizations.
Sponsors of OGC test beds generally come to the table for a couple of
reasons.In the first place it ensures them that their individual needs
will be addressed.Second, it gives them an opportunity to coordinate
satisfaction of their needs with others by co-funding specific work.
Finally, it gives them an environment to test their own work with
others to confirm interoperability and give them a leg up at
Our test bed sponsorship has been in the range of $1.5 to $2M a year, a
figure that is more than matched by in-kind investment on the part of
industry participants.This "in-kind" generally totals two to four
times the sponsors' investment.This is what sponsors find one of the
most attractive features of our Interoperability Program.