Copyright © 2013 Open Geospatial Consortium.
43 Provision of data to test and demonstrate the ePIB scenario and the FPS service in
particular: o Creation of a modified version of Eurocontrol’s DONLON sample data,
shifted from the Atlantic Ocean to Europe for demonstration purposes. o Provision of airport layout features for Chicago O’Hare airport, by
converting public sample data for this airport available in the AMXS format to AIXM 5.1.
o Creation of example Digital NOTAM events temporary crane, unserviceable navaid for Chicago O’Hare and DONLON airports.
6.2.9 ATM-TGS Data Management Service
6.2.9.1 General Context
The Data Management Service DMS was introduced in OWS-9 as a new entity in the OGC architecture. The purpose of this new entity was to enhance the quality of the
exchanges between the information producers or brokers and the information consumers. On the one side, there are the information producers and brokers, among which are the
Web Feature Services WFS and the Event Services ES. On the other side are the clients that consume the information provided by those entities. In OWS-9, the scope of
the DMS action has been limited to the WFS and ES. However, the philosophy applicable to those entities could, in the future, be extended to other information providers and
brokers, such as the Web Processing Service, Web Mapping Service, and Feature Portrayal Service.
Considering information exchange on the ground, the communication technologies available today provide sufficient resources for information transfer without having to
consider much optimization. The bandwidth is generally very high and the communication services are available and reliable. However, especially in the context of
aviation where communications are not limited to the ground but are extended to ground- to-air and air-to ground, new challenges appear e.g. low bandwidth, uncertain
availability of data link between the ground and aircraft. Addressing those challenges is the reason for the introduction of a new entity in Service Oriented Architectures; the Data
Management Service.
The DMS role was to cope with the limitations of the communication link between the ground and the air, looking into more efficient communications means, increasing the
reliability of the data link, and ensuring that the final client e.g. the aircraft was provided with the exact information it needed.
To achieve this, the DMS stood between the client and the other entities, as depicted in Figure 14.
44
Copyright © 2013 Open Geospatial Consortium.
Figure 14 DMS Context Description
6.2.9.2 Functionalities
To manage the information exchange between producersbrokers and consumers of the information, the DMS provided the following functionalities:
Reliable messaging: The DMS established a reliable communication framework
that enhanced data link reliability. This encompassed resending information not received by the client, scheduling the messages and handling network failures.
Filtering: The client had the capability to define certain filtering rules applied to
any information intended to it relayed by the DMS. This allowed removal of certain information in the data set not deemed essential by the client.
Compression: In order to reduce the volume of data sent to the aircraft usually on
data links with low and expensive bandwidth, the client had the capabililty to define a compression algorithm used by the DMS when forwarding information.
In OWS-9, the compression method used was Fast Infoset, based on compression benchmarking undertaken in OWS-8.
Validation: In order to use the data link with maximum efficiency, invalid or
irrelevant information arriving at the DMS should not be forwarded to the client. To achieve this, the DMS included a validation module that performed a check on
the information based on criteria defined with the client. If those criteria were not satisfied, the information was not sent to the client.
Prioritization: In the amount of information that arrives at the DMS, some may be
more important to client. The prioritization module function assessed the level of importance of different data sets intended to the client based on criteria defined by
Copyright © 2013 Open Geospatial Consortium.
45 the client and sent those data sets in order of importance in the event of
concurrent arrival at the DMS.
Synchronization: In the aviation context, to increase situation awareness, the
flight management entity e.g. dispatch may have interest in being aware of the information that is requested and communicated to aircraft it is responsible for.
To tackle that challenge, the DMS offered the capability to dispatch units to subscribe to clients to receive copies or summaries of the information received by
the client.
6.2.9.3 Deployment
