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10.2.4.2 Specific Schedule Request
The Specific Schedule Request message is used to add, delete or replace scheduled
events for SN resources. The following NCCDS constraints apply:
a. All related services (e.g., forward, return, tracking and end-to-end test) for one
SUPIDEN, for one TDRS, and for one continuous period are generally
contained in the same request. However, two independent events for the same
SUPIDEN can be scheduled at the same time whenever this does not result in
resource conflicts.
b. Deletion of a scheduled event may be accomplished only by the MOCC that
has scheduling authority, the NCCDS SO, or the GT (with NCCDS approval or
direction). If the GT deletes an event, this will not result in automatic generation
of messages announcing the deletion.
c. Configuration changes to scheduled events, prior to the scheduled event start
time, require the entire event to be replaced by submitting a Schedule Replace
Request (message type 99, message class 12). Alternatively, the event can be
deleted by submitting a Schedule Delete Request (message type 99, message
class 11) and then a new Schedule Add Request (message type 99, message
class 10) can be transmitted. Ordinarily these two methods will achieve
equivalent results; however, use of the Schedule Replace Request ensures that
the resources allocated to the original event are available to be used to
schedule the replacement. Use of the Schedule Replace Request also leaves
the original event on the schedule if the replacement cannot be scheduled.
d. For add requests, the configuration of services for the event may be specified
either by reference to a set of SSCs or by reference to a prototype event which
then references a predetermined set of SSCs stored in the NCCDS database.
Revision 10 10-15 450-SNUG