1. SM: Data Distribution Service
Message Flow Diagram – Mode 1 (Tasking Mode)
SCOS Client
Data Consumer
SM: Data Distribution Service
SM: Control Service SD
ASC_REQ: request association
ASC_GRANT: grant association
SD/SM association
ASC_ADV: advertise capabilities
HBT_SCHED_SEND: send scan schedule
HBT_SCHED_SEND_ACK: scan schedule ack
AUTH_REQ: request authorisation,
capabilities, status
Control Service/ SM association
AUTH_GRANT: grant authorisation, send capabilities, scan schedule
SCHD_MOD: request mod to schedule
SCHD_MOD: request mod to schedule
scan scheduling
process update to schedule
SCHD_MOD_ACK: ack for sched mod
HBT_SCHD_SEND: send scan schedule
execute scan schedule
Optional – either triggered by user or by SSD if “notify” flag is set
HBT_SCHD_STATUS: request scan status
scan execute
HBT_SCHD_STATUS_ACK: status response
SCHD_STATUS_ACK – sched status response
Piggybacked
HBT_SCHD_STATUS_ACK: status response
DATA_PUB: publish data
DATA_PUB_DM: publish data
data publish
SCHD_COMP_ACK: sched status response
Periodic SD heartbeat/resource advertisement/disconnect
SCHD_COMP_ACK: sched status response
HBT_ASC_RFR: refresh association
SD/SM association currency
HBT_ASC_RFR_ACK: refresh association ack
ASC_DIS_SSD: instruct disassociate
ASC_DIS_SCOS: instruct disassociate
SCAN_TERM: terminate all scanning
SCAN_TERM: terminate all scanning

2. SM: Data Distribution Service
Message Flow Diagram – Mode 2 (Basic Mode)
SCOS Client
Data Consumer
SM: Data Distribution Service
SM: Control Service SD
ASC_REQ: request association
ASC_GRANT: grant association
SSD/SSM association
Sensor capabilities are assumed hardcoded in CR system
Standard scheduled scans hardcoded in CR design
HBT_SCAN: current channel occupancy
scan execute
execute scan schedule
AUTH_REQ: request authorisation, status
AUTH_GRANT: grant authorisation, status
TaskAgent/SSM association and custom scan request
SCHD_MOD: request mod to schedule
process update to schedule
SCHD_MOD_ACK: ack for sched mod
HBT_SCHD_SEND: send scan schedule
Generally schedule hard coded, this method allows for exception scan (exception is “scheduled” as once-off)
execute scan schedule
DATA_PUB: publish data
DATA_PUB_DM: publish data
DATA_PUB_CL: publish data
SCHD_COMP_ACK: sched status response
Periodic SSD heartbeat/resource advertisement/disconnect
HBT_ASC_RFR: refresh association
SSD/SSM association currency
HBT_ASC_RFR_ACK: refresh association ack
ASC_DIS_SSD: instruct disassociate
ASC_DIS_SCOS: instruct disassociate

3. HBT_SCHED_STATUS_ACK
SD State Diagram – Mode 0 (Tasking Mode)
Registered
poweron
startup
Ready
Off
HBT_SCHED_SEND
HBT_SCHED_SEND_ACK
POWEROFF
shutdown
advertise timer exp
ASC_ADV
ASC_REQ
ASC_GRANT
Active
HBT_SCHED_SEND
HBT_SCHED_SEND_ACK
Pending
scan perform timer exp
schedule lock
Scanning
Heartbeat timer exp
ASC_DIS_SSD
scan complete
HBT_SCHED_STATUS_ACK
DATA_PUB
SCAN_TERM
TERM_ACK
event external trigger
action response to event
state change direction
State
stable system state

4. SSD State Diagram - Mode 1 (Basic Mode)
poweron
startup
Ready
Off
POWEROFF
shutdown
advertise timer exp
ASC_ADV
ASC_REQ
ASC_GRANT
HBT_SCHED_SEND
HBT_SCHED_SEND_ACK
Automatic Scanning
Associated
Heartbeat timer exp
ASC_DIS_SSD
scan complete
HBT_SCHED_STATUS_ACK
HBT_SCHED_SEND
HBT_SCHED_SEND_ACK
Tasked Scanning
event external trigger
action response to event
state change direction
State
stable system state
scan complete
HBT_SCHED_STATUS_ACK
DATA_PUB