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Inc. All Rights Reserved.
Current History WFS: within this configuration a single feature is published
representing each real world object. Each feature contains only BASELINE and TEMPDELTA timeslices that are valid now and in the future.
Full History WFS: within this configuration a single feature is published
representing each real world object. Each feature contains all BASELINE and TEMPDELTA timeslices that have ever been published.
1 Feature – 1 Timeslice WFS: within this configuration multiple features are
published that represent the real world objects. Each feature contains only one timeslice: BASELINE, TEMPDELTA or PERMDELTA that representing the
state of the real world object or an event that resulted in permanent or temporary change to the feature over a specified time period.
7.1.1.1.2 WFS-T 2.0 transactional
A separate transactional WFS 2.0 instance was established to support the authoritative data source and event architecture threads. The WFS-T was established to support the
insert of features containing TEMPDELTA timeslices representing i SAA Activation Schedules create, modify, approve, disapprove, ii Navaid Unservicable, iii Runway
Closure and iv Airport Surface Contamination.
The WFS-T was integrated into the data maintenance architecture for the consolidated database. On insert of a Feature containing a TEMPDELTA timeslice a series of
processes are then triggered to auto generate additional information to publish the data via the WFS and Event Publisher in real-time.
7.1.1.1.3 Event Publisher
The Event Publisher is composed of two components:
GO Publisher Agent: a server-side bulk data publishing system that generates
event messages
Event Pusher: this registers with one or more event services as an event source
and pushes the messages generated to the event service brokers Publication of events is triggered by the insertion of a timeslice into the database. GO
Publisher Agent generates a Digital NOTAM Event which is published into a directory on the server. The Event Pusher polls this directory and on receipt of an Event message, it
then pushes the message to the Event Service Brokers.
7.1.1.2 Component functionality
No new component functionality was developed for either GO Publisher WFS or the Event Publisher during OWS-8. GO Publisher WFS currently implements a large
proportion of the OGC WFS 2.0 specification Table x and the Event Publisher continues to have sufficient functionality to connect to the IfGI and IDS Event Services.
Copyright © 2011 Open Geospatial Consortium,
Inc. All Rights Reserved.
17
Within OWS-8, the aim was to further evaluate the effectiveness of the basic mandatory WFS 2.0 operations and full filter encoding FE 2.0 to retrieve AIXM 5.1 data for the
various flight planning and dispatch scenarios identified.
7.1.1.3 Data available via the components
The OWS-8 consolidated database consists of data containing BASELINE and TEMPDELTA timeslices from the following sources:
EANS: the EANS AIXM 5.1 was made accessible via the Comsoft WFS. Some
of the feature types relevant for the scenario were harvested and loaded into the consolidated database using GO Loader.
EurocontrolLFV FAA Airports GIS data and AMDB Obstacles data: these
data provided for use within OWS-6 and 7 were published from the original project databases as AIXM 5.1 and loaded into the consolidated database using
GO Loader.
Eurocontrol Digital Snowtam Trial 2011: A global dataset of AirportHeliport
AIXM 5.1 features were harvested on an ad hoc basis from the WFS established for the Digital Snowtam trial.
FAA NASR Subscriber data: pre-operational data feed providing access to
AIXM 5.0 SAA messages updated every 56 days inline with the AIRAC cycle. These were loaded into initially into an SAA 5.0 database then published out as
AIXM 5.1 and loaded into the consolidated database using GO Loader.
FAA SAMS SUA Data feed: operational data feed providing access to SAA
Activation schedules .csv updated every minute.
Test Events: a set of example test events were created to support the various
scenarios that were inserted into the consolidated database via the WFS-T 2.0
7.1.1.4 Accomplishments
Several key accomplishments were developed within OWS-8 within the data maintenance and publication architecture developed by Snowflake:
Consolidated data from multiple sources, published using different AIXM 5.1 extension schemas into a single authoritative database and provided access to
these data via the WFS 2.0 and Event Publisher Extended the database to include some example reverse associations for
AirportHeliport, Runway, Runway Element and Airspace features and tested the benefits of reverse associations for improved data retrieval
Configured the WFS-T to support the authoritative data source and flight planning scenarios enabling users to insert TEMPDELTA timeslices create, authorize,
modify, canceldisapprove into the database. On insert additional processes were triggered to auto generate additional properties i.e. sequenceNumber,
correctionNumber, gml:id for publication via Event Publisher and WFS
7.1.1.5 Challenges
Two key challenges were identified with retrieving AIXM features from the WFS 2.0.
