Specifications:

(Note, 0.2.0 is under development and is still fluid. Expect changes, and do assume it is fixed. We have posted pre-releases for pontetial feedback from users. See below for planned work.)

Spec. File	Docs	Notes
0.2.0pre1	xs3p       javadoc	Prototype GSML 0.2 specification. Currently under development, hence the "pre" release. Design and structure issues are being worked out as we implement in Mercury 1.2.

Overview:
Major upgrades were made to the GSML specification from 0.1 to 0.2. Session and network level GSML messages are now included. The specification is now more formally written in XML Schema. The API and protocol for using GSML is documented within the specification itself. We have used several off-the-shelf tools for viewing the schema and documentation, xs3p and javadoc (compiles the code generated by Castor, a databinding tool).

The Mercury source code uses off-the-shelf data binding software, Castor, to automatically generate Java object code from the XML schema specification file. Approximately 50,000 lines of code are generated with the sub 1k line specification file. This Java object code is then compilied into the ComGsml component of Mercury to enable applications easy use of Gsml messaging over TCP, SSL, and UDP sockets.

The GSML specification is still a prototype and we expect changes and upgrades for the near term. Mercury development effort to support the session and network levels is underway in 1.2.*. These efforts will flush out more GSML requirements and changes. Also, as Mercury is deployed, we expect other ground station teams to provide vital recommendations to GSML improvement.

Planned Development:
The following describes planned work on the GSML specification. Feel free to offer input on the mgsn-development mailing list.

1. SessionControllerState will be reworked. It is currently in its 0.1, flat, attribute laden format.
2. Environmental parameters such as temperature and power related telemetry will be incorporated to hardware level documents.
3. Commands for adding/editing/removing/listing of targets (satellites) will be added to the session level.
4. The Session document needs parameters that the GS defines after it has been scheduled (such as dataserver port number).