Space Link Extension - Service Management - CCSDS

DRAFT RECOMMENDED STANDARD FOR SPACE LINK EXTENSION SERVICE MANAGEMENT
resources were potentially available at the time of the CTSP invocation, but will not
be committed until and unless the package is accepted by UM (as defined by the
schedulingMode parameter in the Service Agreement);
These following subsections more fully describe the Service Package operations.
2.2.3.2 CREATE_SERVICE_PACKAGE
UM invokes a CREATE_SERVICE_PACKAGE operation to request a contact at a time
specified within the invocation. A CreateServicePackageInvocation (CSP-I)
message contains essentially the same information that is contained in the Service Package
that results from the invocation, with the following exceptions:
a) For each space link carrier in each scenario, UM may defer selection of the antenna(s) to
CM, or constrain or influence the selection. Antenna selection by CM is based on
availability and visibility at the time of the requested contact of an antenna identified in
the Service Agreement, and conformance with the space link characteristics of the
referenced Carrier Profile. UM may constrain the selection to a subset of the antennas
identified in the Service Agreement, and—whether thus constrained or not—may
indicate a subset of preferred antennas. CM will first attempt to schedule a preferred
antenna if indicated; if this is not possible, it will attempt to schedule any acceptable
antenna.
b) For each space link carrier in each scenario, the preferred start time,
minimum/preferred contact durations, and optional start lag/lead times are specified
instead of the specific start and stop times found in the Service Package itself. These
parameters allow CM latitude in fitting the request into the schedule.
c) Transfer service instances may be active through changes across multiple scenarios.
Each scenario in a CSP-I contains a reference to a Space Link Session Profile,
containing Carrier Profiles, which in turn reference one or more Transfer Service
Profiles, for which corresponding transfer service instances may be enabled. The
resulting service package contains, in effect, a pool of transfer service instances that
may be used by multiple scenarios. Each transfer service instance may be referenced
with a service mapping by carriers in more than one scenario. This allows UM to
request transfer service instances that will persist if different scenarios are selected
while the Service Package is in execution.
d) The transfer service instances within the pool contain offset start and offset stop times
instead of specific start and stop times. These offsets are relative to the start and stop
times of the carriers with which the transfer service instances are associated.
e) A CSP may defer specification of transfer service instances. If an incomplete (that is,
without transfer services specified) CSP-I is accepted by CM, UM must
subsequently fill in the missing elements of the Service Package (i.e., the specific
SLE transfer services to be provided) by invoking a complete
REPLACE_SERVICE_PACKAGE operation prior to the start time of the Service
CCSDS 910.11-R-2 Page 2-7 March 2008