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Revision 10 10-36 450-SNUG
Message ID Message
Type/
Class
OPM 01
Special
Instruction or
Request
OPM 02
Reacquisition
Request
Table 10-12. Real-time Message Flow Between the NCCDS and the GTs
Message Length and
Operational
Characteristics
03/01 Used in message
exchange between
controllers
Not used in automatic
processing/control
Message
Generation
Frequency
Message Generation
Conditions
Messages from the NCCDS to the GTs
This message is used to send
free-form alphanumeric text
from the NCCDS to GTs
Required Processing Destination System Response
No processing required
GT prints this message and
displays it on a TOCC
console
03/02 Real-time control message Initial link acquisition failure NCCDS reformats and
validates the MOCC GCMR
(98/03)
GT response time is up to 20
seconds (forward) and 10
seconds (return) of OPM receipt
and acceptance for all services
Link unlocked GT sends an OPM 63
(Acquisition Failure Notification)
to the NCCDS if the acquisition
process fails
Link acquisition failure during a
customer platform real-time
configuration
GT verifies and validates the
OPM and initiates the
reacquisition process. It
should be noted for
coherent service mode, a
forward reacquisition will
cause both forward and
return services to be
reacquired
GT sends an OPM status
message (OPM 62) upon
successful reacquisition
completion