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Copyright © 2013 Open Geospatial Consortium.
how modules are to be used by the DMS when forwarding or receiving messages from the aircraft client. An aircraft client may communicate with a DMS using multiple
communication patterns including Features negotiation, Request-response, Subscription Request, and Event Notifications. Once configured by the aircraft client, the DMS
proxied the request-response pattern to a WFS. Subscription requests and notifications are proxied to an Event Service.
6.2.10.4 Component Functionality 6.2.10.4.1 Data Filtering Module
The Data Filtering Module was a client-configurable Module Feature designed to extend the message filtering capabilities of ground services. Message content was filtered by the
module using an aircraft client provided XSLT string as a guide. By allowing clients to provide their own filtering instructions to the DMS, the Filtering Module could be
customized to fit the client’s individual needs.
6.2.10.4.2 Data Validation Module
The Data Validation Module is a client-configurable Module Feature designed to track the validity of messages being transmitted to the aircraft client. The module determined
the currency of messages received which is provided by TimeSlice data included in AIXM messages. Depending on a client’s session profile, non-current messages were
either dropped or flagged and forwarded to the client. The message latency of transmission from DMS to reception by the client was evaluated against a configurable
variance amount stored in the aircraft client’s session profile. This provided a metric to determine the timeliness of data transmission to clients. The DMS collected and stored
data from the Data Validation Module to track the number of non-current messages received or transmitted and the number of messages that exceed the client’s latency
tolerance.
6.2.10.4.3 Data Prioritization Module
The Prioritization Module was a client-configurable Module Feature designed to ensure that messages of high importance were delivered to the aircraft client when transmitted
over bandwidth restricted links. This module prioritized messages based on settings in a client’s DMS session profile. Using this configuration, the Prioritization Module assigned
priority levels to messages scheduled to be transmitted to a client. The session profile stored a list of message types that were considered higher priority than all other
messages. When configured, the DMS created a queue for all messages being transmitted to a client. When a message is removed from the queue and transmitted to the client, the
DMS waited for the client’s acknowledgement of message reception before transmission of the next message in the queue. When new messages are added to the transmission
queue, messages that are defined as high priority were sent to the front of the queue. Messages defined as low priority were added at the end of the transmission queue.
Copyright © 2013 Open Geospatial Consortium.
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6.2.10.4.4 Data Provenance Module
